Page 2 : Computer, • What is Computer?, •, , Computer is an electronic device which takes data as input, processes it and produces the results as, output.

Page 3 : Central Processing Unit (CPU), •, , •, •, •, •, •, , A Central Processing Unit is also called a processor, central processor, or microprocessor. It carries, out all the important functions of a computer. It receives instructions from both the hardware and, active software and produces output accordingly. It stores all important programs like operating, systems and application software. CPU also helps Input and output devices to communicate with, each other. it is often referred to as the brain of the computer., CPU is installed or inserted into a CPU socket located on the motherboard., Generally, a CPU has three components:, ALU (Arithmetic Logic Unit), Control Unit, Memory or Storage Unit

Page 4 : • CU(Control Unit):- It takes instructions from memory and then decodes and executes these, instructions. So, it controls and coordinates the functioning of all parts of the computer. The, Control Unit's main task is to maintain and regulate the flow of information across the processor., , • ALU(Arithmetic Logic Unit):- It is the arithmetic logic unit, which performs arithmetic and, logical functions. Arithmetic functions include addition, subtraction, multiplication division, and, comparisons. Logical functions mainly include selecting, comparing, and merging the data. A CPU, may contain more than one ALU. Furthermore, ALUs can be used for maintaining timers that help, run the computer., , • Memory or Storage Unit/ Registers:- It is called Random access memory (RAM). It, temporarily stores data, programs, and intermediate and final results of processing. So, it acts as a, temporary storage area that holds the data temporarily, which is used to run the computer., , • What is CPU Clock Speed?, •, , The clock speed of a CPU or a processor refers to the number of instructions it can process in a, second. It is measured in gigahertz. For example, a CPU with a clock speed of 4.0 GHz means it can, process 4 billion instructions in a second., , • Types of CPU:, •, •, , CPUs are mostly manufactured by Intel and AMD, each of which manufactures its own types of, CPUs. In modern times, there are lots of CPU types in the market., Single Core CPU, Dual Core CPU, Quad Core CPU

Page 5 : Input Device, •, •, •, •, •, •, •, •, •, •, •, •, •, •, , An input device allows data such as text, images, video or sound to be entered into a, computer system., Following are some of the important input devices which are used in a computer –, Keyboard, Mouse, Joy Stick, Light pen, Track Ball, Scanner, Graphic Tablet, Microphone, Magnetic Ink Card Reader(MICR), Optical Character Reader(OCR), Bar Code Reader, Optical Mark Reader(OMR)

Page 6 : Booting in Operating System, •, , •, •, •, , •, , Booting is the process of starting a computer. It can be initiated by hardware such as a, button press or by a software command. After it is switched on, a CPU has no software in, its main memory, so some processes must load software into memory before execution., This may be done by hardware or firmware in the CPU or by a separate processor in the, computer system., Types of Booting, There are two types of booting in an operating system, Cold Booting: When the computer starts for the first time or is in a shut-down state and, switch on the power button to start the system, this type of process to start the, computer is called cold booting. During cold booting, the system will read all the, instructions from the ROM (BIOS) and the Operating System will be automatically get, loaded into the system. This booting takes more time than Hot or Warm Booting., Warm Booting: Warm or Hot Booting process is when computer systems come to no, response or hang state, and then the system is allowed to restart during on condition. It, is also referred to as rebooting. There are many reasons for this state, and the only, solution is to reboot the computer. Rebooting may be required when we install new, software or hardware. The system requires a reboot to set software or hardware, configuration changes, or sometimes systems may behave abnormally or may not, respond properly. In such a case, the system has to be a force restart. Most, commonly Ctrl + Alt + Del

Page 7 : Software, •, , Software is a set of programs (sequence of instructions) that allows the users to, perform a well-defined function or some specified task., , •, •, , Types of Software, Software's are broadly classified into two types, i.e., System Software and Application, Software., , • System Software, •, , System software is a computer program that helps the user to run computer hardware, or software and manages the interaction between them. Essentially, it is software, that constantly runs in the computer background, maintaining the computer hardware, and computer's basic functionalities, including the operating system, utility software,, and interface. In simple terms, you can say that the system acts as a middle man that, checks and facilitates the operations flowing between the user and the computer, hardware.

Page 9 : •, , The further classifications of system software are as follows:, , •, , 1. Operating System, , •, , It is a group of software that handles the execution of programs and offers general services for the, application that runs over the computer. There are various types of operating systems available in, the market, such as embedded operating systems, real-time OS, distributed OS, single or multi-user, operating system, mobile, Internet, and various others., , •, , Some of the commonly used examples of operating systems are given below., , •, •, •, •, •, •, •, •, •, •, , Microsoft Windows, Apple's iOS, Apple's MacOS, Android, CentOS, Linus, Ubuntu, Unix, 2. Device Drivers, In computing, the device driver is a type of software that operates or controls some specific, hardware devices linked to your system., 3. Firmware, In electronic systems and computing, firmware is a type of permanent software embedded in the, system's ROM (read-only memory) to provide low-level control for some particular system device, hardware, , •, •

Page 10 : Application Software, •, , Application programs or software applications are end-user computer programs developed, primarily to provide specific functionality to the user. The applications programs assist the user in, accomplishing numerous tasks such as doing online research, completing notes, designing, graphics, managing the finances, watching a movie, writing documents, playing games, and many, more., , •, , a. Word Processors, , •, , Word processor applications are globally used for documentation, making notes, and typing, data. It also helps the end-users store and format data. They also enable the users to print their, documents., Some examples of Word Processor software's are as follows:, MS Word (Microsoft), iWork-Pages (Apple), Corel WordPerfect, Google Docs, , •, •, •, •, •

Page 11 : •, , Database Software, , •, •, •, •, •, •, •, •, •, •, , Database software is used to create, manage, modify and organize a massive amount of data quickly, retrieved. Another name for database software is Database Management System (DBMS)., Such software helps companies in their data organization. Common examples of Database Software's are, Oracle, MS Access, SQLite, Microsoft SQL Server, FileMaker, dBase, MariaDB, MySQL, , •, , c. Multimedia Software, , •, , This software enables the users to play, create or record images, music, and video files. Different graphic, designing companies widely use multimedia software to make animation, images, posts, packaging,, marketing creative, gif, or even video editing., Common examples of Multimedia Software's are given below, Adobe Photoshop, Windows Movie Maker, Adobe Illustrator, Picasa, Windows Media Player, Corel Draw, , •, •, •, •, •, •, •

Page 12 : •, , d. Web Browsers, , •, , These are a type of software that is globally used to browse the Internet. Web browsers help, the users in positioning as well as fetching data across the web. Common examples of web, browsers are given below:, Chrome, Mozilla Firefox, Microsoft Internet Explorer, Opera, Microsoft Edge, UC Browser, Apple Safari, , •, •, •, •, •, •, •, , • 1. Freeware, •, , •, •, •, •, •, •, •, , Freeware software is available free of cost for an unlimited time. Any user can easily, download their respective software from the Internet and start using them instantly, without paying any charges or fees. Software development companies mostly design and, develop freeware software as a strategy to reach out to more people. Typical examples of, Freeware Software are as follows:, Adobe Reader, Zoom, Skype, ImgBurn, Audacity, Whatsapp, Anydesk

Page 13 : Utility Software, • Utility software works as an interface between system software and application, software. Utility software is a third-party tool designed to reduce maintenance issues and, detect errors in the computer system. It comes with the operating system in your, computer system., , • Here are some specific features of utility software:, •, •, •, •, •, •, , It helps users to protect against threats and viruses., It helps to reduce disk size such as WinRAR, WinZip., It works as a Windows Disk Management service and helps in a disk partition., It facilitates users to back up the old data and enhance the security of the system., It works as a de-fragmentation of a disk to organize the scattered files on the drive., It helps to recover the lost data., , • What is a Language Processor?, •, , •, •, , Mostly, high-level languages like Java, C++, Python, and more are used to write the, programs, called source code, as it is very uninteresting work to write a computer, program directly in machine code. These source codes need to translate into machine, language to be executed because they cannot be executed directly by the computer., Hence, a special translator system, a language processor, is used to convert source code, into machine language., There are mainly three kinds of language processors, which are discussed below:, 1. Compiler, 2. Interpreter, 3. Assembler

Page 14 : Introduction to Compiler, •, •, •, •, , •, , A compiler is a translator that converts the high-level language into the machine, language., High-level language is written by a developer and machine language can be understood, by the processor., Compiler is used to show errors to the programmer., The main purpose of compiler is to change the code written in one language without, changing the meaning of the program., , Interpreter: An interpreter is a computer program that allows a computer to interpret, or understand what tasks to perform. The programs written with the help of using one, of the many high-level programming languages are directly executed by an interpreter, without previously converting them to an object code or machine code, which is done, line by line or statement by statement. When the interpreter is translating the source, code, it displays an error message if there is an error in the statement and terminates, this statement from translating process. When the interpreter removed errors on the, first line, then it moves on to the next line.

Page 15 : Assembler, •, , Assembler: An assembler converts programs written in assembly language into, machine code. It is also referred to assembler as assembler language by some users., The source program has assembly language instructions, which is an input of the, assembler. The assemble translates this source code into a code that is understandable, by the computer, called object code or machine code.

Page 16 : Computer Viruses/Anti Viruses, • Computer viruses are unwanted software programs or pieces of code that interfere, with the functioning of the computer. Once it enters your system, it can replicate to, produce copies of itself to spread from one program to another program and from one, infected computer to another computer., , • Antiviruses:- There are many antiviruses, which are programs that can help you protect, your machine from viruses. It scans your system and cleans the viruses detected during, the scan. Some of the popular antiviruses include Avast, QuickHeal, McAfee, Kaspersky,, etc.

Page 17 : Operating System, •, , •, •, , An Operating System (OS) is a software that acts as an interface between computer, hardware components and the user. Every computer system must have at least one, operating system to run other programs. Applications like Browsers, MS Office, Notepad, Games, etc., need some environment to run and perform its tasks., Types of Operating Systems, An operating system is a well-organized collection of programs that manages the, computer hardware. It is a type of system software that is responsible for the smooth, functioning of the computer system.

Page 18 : Real Time Operating System, •, , In Real-Time Systems, each job carries a certain deadline within which the job is supposed, to be completed, otherwise, the huge loss will be there, or even if the result is produced,, it will be completely useless., , •, , The Application of a Real-Time system exists in the case of military applications, if you, want to drop a missile, then the missile is supposed to be dropped with a certain, precision., , •

Page 19 : Time-Sharing Operating System, •, , In the Time Sharing operating system, computer resources are allocated in a timedependent fashion to several programs simultaneously. Thus it helps to provide a large, number of user's direct access to the main computer. It is a logical extension of, multiprogramming. In time-sharing, the CPU is switched among multiple programs given, by different users on a scheduled basis., , •, , A time-sharing operating system allows many users to be served simultaneously, so, sophisticated CPU scheduling schemes and Input/output management are required., Time-sharing operating systems are very difficult and expensive to build., , •

Page 20 : Distributed Operating System, •, , The Distributed Operating system is not installed on a single machine, it is divided into, parts, and these parts are loaded on different machines. A part of the distributed, Operating system is installed on each machine to make their communication possible., Distributed Operating systems are much more complex, large, and sophisticated than, Network operating systems because they also have to take care of varying networking, protocols.

Page 21 : GUI Operating System, •, •, , What is GUI OS?, GUI stands for Graphical User Interface. It is a visual representation of communication, presented to the user for easy interaction with the machine. The actions in a GUI are, usually performed through direct manipulation of graphical elements like buttons and, icons. Communication can be performed by interacting with these icons rather than the, usual text-based or command-based communication.

Page 22 : Android Operating System, •, , •, , •, •, , Android is a mobile operating system based on a modified version of the Linux kernel and other, open-source software, designed primarily for touchscreen mobile devices such as smartphones and, tablets. Android is developed by a partnership of developers known as the Open Handset Alliance, and commercially sponsored by Google. It was disclosed in November 2007, with the first, commercial Android device, the HTC Dream, launched in September 2008., It is free and open-source software. Its source code is Android Open Source Project (AOSP), primarily, licensed under the Apache License. However, most Android devices dispatch with additional, proprietary software pre-installed, mainly Google Mobile Services (GMS), including core apps such as, Google Chrome, the digital distribution platform Google Play and the associated Google Play Services, development platform., , Features of Android Operating System

Page 23 : Bharat Operating System Solutions(BOSS), •, , Bharat Operating System Solutions (BOSS GNU/Linux) is an Indian Linux distribution derived, from Debian. BOSS Linux is officially released in four editions: BOSS Desktop (for personal use, home, and office), EduBOSS(for schools and education community), BOSS Advanced Server and BOSS MOOL., The latest stable version 8.0 ("Unnati"), was released on 11 July 2019., , •, , It is developed by Centre for Development of Advanced Computing (C-DAC) in order for enhancing and, gain benefit from the usage of Free and Open Source Software throughout India. BOSS Linux is a key, deliverable of National Resource Centre for Free and Open Source Software (NRC-FOSS). It has, enhanced desktop environment integrated with Indian language support and other software., , Symbian OS, •, , Symbian OS: Symbian operating system is a mobile operating system that provides a high-level of, integration with communication. The Symbian operating system is based on the java language. It, combines middleware of wireless communications and personal information management (PIM), functionality. The Symbian operating system was developed by Symbian Ltd in 1998 for the use of, mobile phones. Nokia was the first company to release Symbian OS on its mobile phone at that time.

Page 24 : UNIX operating system, •, , UNIX is a powerful Operating System initially developed by Ken Thompson, Dennis, Ritchie at AT&T Bell laboratories in 1970. It is prevalent among scientific, engineering,, and academic institutions due to its most appreciative features like multitasking,, flexibility, and many more. In UNIX, the file system is a hierarchical structure of files and, directories where users can store and retrieve information using the files.

Page 25 : Linux os, , • Linux is an open-source operating system like other operating systems such as, Microsoft Windows, Apple Mac OS, iOS, Google android, etc. An operating system is a, software that enables the communication between computer hardware and software., •, , The Linux OS was developed by Linus Torvalds in 1991. Nowadays, Linux is the fastestgrowing OS. It is used from phones to supercomputers by almost all major hardware, devices., , Windows, •, , •, , Windows is a graphical operating system developed by Microsoft. It allows users to, view and store files, run the software, play games, watch videos, and provides a way to, connect to the internet. It was released for both home computing and professional, works., It was released for both home computing and professional functions of Windows on 10, November 1983. Later, it was released on many versions of Windows as well as the, current version, Windows 11.

Page 26 : Solaris Operating System, •, •, , Solaris is a proprietary operating system based on UNIX. Its design emphasizes simplicity. It, allows you to update the complete cloud installation with a single command for ease of, maintenance., Solaris OS is also very secure. The User and Process Rights Management reduces hacking, threats by requiring users and applications to have the minimum capabilities required to, complete their duties, , Functions of Operation System, •, •, •, •, •, •, •, •, •, •, •, •, •, , An operating system is a program that acts as a user-computer GUI (Graphical user interface)., It controls the execution of all types of applications., The operating system performs the following functions in a device., Instruction, Input/output Management, Memory Management, File Management, Processor Management, Job Priority, Special Control Program, Scheduling of resources and jobs, Security, Monitoring activities, Job accounting

Page 27 : • Input/output Management: What output will come from the input given by the user,, the operating system runs this program. This management involves coordinating various, input and output devices. It assigns the functions of those devices where one or more, applications are executed., , • Device management:- Device management in an operating system means controlling, the Input/Output devices like disk, microphone, keyboard, printer, magnetic tape, USB, ports, camcorder, scanner, other accessories, and supporting units like supporting units, control channels, , • Memory Management: The operating system handles the responsibility of storing any, data, system programs, and user programs in memory. This function of the operating, system is called memory management., , • File Management: The operating system is helpful in making changes in the stored files, and in replacing them. It also plays an important role in transferring various files to a, device., , • Processor Management: The processor is the execution of a program that, accomplishes the specified work in that program. It can be defined as an execution unit, where a program runs.

Page 28 : Disk Management Tools, • Disk Management Tools, •, •, •, •, •, •, •, •, •, •, , Disk management tools are utility software that is used to manage data on disk by, performing various functions on it. Moreover, they perform functions like partitioning, devices, manage drives, disk checking, disk formatting, etc., Types of Disk Management Tools, 1. Disk Cleanup Tools, These tools clean up the unnecessary and unwanted files on the system. Furthermore,, this deletion of files thus helps to clean up the disk space. Moreover, it prevents, unnecessary clutter and protects privacy., 2. Disk Compression Tools, The disk compression tools or disk compression utility increases the amount of space on a, disk by decreasing the size of information. The utility compresses the information while, storing it on this disk., 3. Disk Defragmenter, This utility software helps to reduce the fragmentation and hence, reduces the access, speed. Defragmenting refers to rearranging files and storing them in contiguous memory, locations, 4. Backup Software, This keeps a copy of all the information on a disk. Whenever some disk failure occurs or, files are deleted accidentally, it restores the files. Restoring the whole disk is called disk, cloning.

Page 29 : Open Source Software, •, , A software whose source code is freely distributed with a license to study, change and further, distributed to anyone for any purpose is called open source software. Open source software is, generally a team effort where dedicated programmers improve upon the source code and share the, changes within the community., , •, , Freeware, , •, , A software that is available free of cost for use and distribution but cannot be modified as its source, code is not available is called freeware. Examples of freeware are Google Chrome, Adobe Acrobat, PDF Reader, Skype, etc., , •, , Shareware, , •, , A software that is initially free and can be distributed to others as well, but needs to be paid for after, a stipulated period of time is called shareware. Its source code is also not available and hence, cannot be modified., , •, , Proprietary Software, , •, , Software that can be used only by obtaining license from its developer after paying for it is, called proprietary software. An individual or a company can own such proprietary software. Its, source code is often closely guarded secret and it can have major restrictions like −, No further distribution, Number of users that can use it, Type of computer it can be installed on, example multitasking or single user, etc., For example, Microsoft Windows is a proprietary operating software that comes in many editions, for different types of clients like single-user, multi-user, professional, etc., , •, •, •, •

Page 30 : Word processor, •, •, , The word “word processor” means it processes words with pages and paragraphs., Microsoft Word is word processing software. It is developed by Microsoft and is part of Microsoft, Office Suite. It enables you to create, edit and save professional documents like letters and reports., , •, , Examples or Applications of a Word Processing Software :, , •, •, •, •, •, •, •, •, , Wordpad, Microsoft Word, Lotus word pro, Notepad, WordPerfect (Windows only),, AppleWorks (Mac only),, Work pages, Open Office Writer

Page 31 : Presentation, •, , •, •, •, •, , In computing, a presentation program (also called presentation software) is, a software package used to display information in the form of a slide show. It has three, major functions:, an editor that allows text to be inserted and formatted, a method for inserting and manipulating graphic images and media clips, a slide-show system to display the content, Microsoft PowerPoint is a popular presentation and slideshow program that allows users, to give presentations in offices and schools regardless of topics.

Page 32 : Spreadsheet, •, •, , •, , A spreadsheet is a computer application for computation, organization, analysis, and storage of data in tabular form., People all across the world use spreadsheets to create tables for personal and business, usage. You can also use the tool’s features and formulas to help you make sense of your, data. You could, for example, track data in a spreadsheet and see sums, differences,, multiplication, division, and fill dates automatically, among other things. Microsoft Excel,, Google sheets, Apache open office, LibreOffice, etc are some spreadsheet software., Among all these software, Microsoft Excel is the most commonly used spreadsheet tool, and it is available for Windows, macOS, Android, etc., A collection of spreadsheets is known as a workbook. Every Excel file is called a, workbook.

Page 33 : Database management system, • What is Database?, •, •, •, •, , The database is a collection of inter-related data which is used to retrieve, insert and, delete the data efficiently. It is also used to organize the data in the form of a table, For example: The college Database organizes the data about the admin, staff, students, and faculty etc., Using the database, you can easily retrieve, insert, and delete the information., Database Management System, , • Database management system is a software which is used to manage the database., •, •, , For example: MySQL, Oracle, etc are a very popular commercial database which is used, in different applications., DBMS provides an interface to perform various operations like database creation,, storing data in it, updating data, creating a table in the database and a lot more., It provides protection and security to the database. In the case of multiple users, it also, maintains data consistency.

Page 34 : School Management Information System, •SIMS (School Information Management System) is a student information system, i.e. a, school management information system, currently developed by Education Software, Solutions. It is the most widely used MIS in UK schools, claiming over 80% market share, across the primary and secondary sectors., •Student Management System (SMS) is a solution tool that is designed to track, maintain, and manage all the data generated by a School, including the grades of a student, their, attendance, their interpersonal activities records, etc.,

Page 35 : Inventory Management System, •, , Inventory management software is a software system for tracking inventory levels, orders, sales and, deliveries. It can also be used in the manufacturing industry to create a work order, bill of, materials and other production-related documents., , Payroll System, •, , A Payroll System is a software to automate the payroll process. These systems can be integrated, with leave and attendance tracking systems and employee self-service portal and are used to keep, track of employee’s working hours, calculate salaries, calculate taxes and deductions, print payslip,, etc., , Financial accounting, •, , Financial accounting is the field of accounting concerned with the summary, analysis and reporting, of financial transactions related to a business. This involves the preparation of financial, statements available for public use. Stockholders, suppliers, banks, employees, government, agencies, business owners, and other stakeholders are examples of people interested in receiving, such information for decision making purposes.

Page 36 : Number System, • Number System, •, , The technique to represent and work with numbers is called number system. Decimal number, system is the most common number system. Other popular number systems include binary number, system, octal number system, hexadecimal number system, etc., , • Types of Number System, •, 1., 2., 3., 4., , In the digital computer, there are various types of number systems used for representing, information., Binary Number System, Decimal Number System, Hexadecimal Number System, Octal Number System

Page 37 : Binary Number System, •, , •, •, , Generally, a binary number system is used in the digital computers. In this number system, it carries, only two digits, either 0 or 1. There are two types of electronic pulses present in a binary number, system. The first one is the absence of an electronic pulse representing '0'and second one is the, presence of electronic pulse representing '1'. Each digit is known as a bit. A four-bit collection (1101), is known as a nibble, and a collection of eight bits (11001010) is known as a byte. The location of a, digit in a binary number represents a specific power of the base (2) of the number system., Examples:, (10100)2, (11011)2, (11001)2, (000101)2, (011010)2, , •, , Decimal Number System, , •, , Decimal number system is a base 10 number system having 10 digits from 0 to 9. This means that, any numerical quantity can be represented using these 10 digits. Decimal number system is also, a positional value system., we have three numbers – 734, 971 and 207. The value of 7 in all three numbers is different−, In 734, value of 7 is 7 hundreds or 700 or 7 × 100 or 7 × 102, In 971, value of 7 is 7 tens or 70 or 7 × 10 or 7 × 101, In 207, value 0f 7 is 7 units or 7 or 7 × 1 or 7 × 100, , •, •, •, •

Page 38 : • Binary Number System, •, , •, , •, •, •, •, , The easiest way to vary instructions through electric signals is two-state system – on and, off. On is represented as 1 and off as 0, though 0 is not actually no signal but signal at a, lower voltage. The number system having just these two digits – 0 and 1 – is, called binary number system., Each binary digit is also called a bit. Binary number system is also positional value, system, where each digit has a value expressed in powers of 2, as displayed here., , decimal equivalent of this number is sum of product of each digit with its positional, value., 110102 = 1×24 + 1×23 + 0×22 + 1×21 + 0×20, = 16 + 8 + 0 + 2 + 0, = 2610

Page 39 : • Octal Number System, •, , Octal number system has eight digits – 0, 1, 2, 3, 4, 5, 6 and 7. Octal number system is also a, positional value system with where each digit has its value expressed in powers of 8, as shown here, −, , •, •, •, •, , Decimal equivalent of any octal number is sum of product of each digit with its positional value., 7268 = 7×82 + 2×81 + 6×80, = 448 + 16 + 6, = 47010, , • Hexadecimal Number System, •, , Hexadecimal number system has 16 symbols – 0 to 9 and A to F where A is equal to 10, B is equal, to 11 and so on till F. Hexadecimal number system is also a positional value system with where each, digit has its value expressed in powers of 16, as shown here −, , •, , Decimal equivalent of any hexadecimal number is sum of product of each digit with its positional, value., 27FB16 = 2×163 + 7×162 + 15×161 + 10×160, = 8192 + 1792 + 240 +10, = 1023410, , •, •, •

Page 40 : ASCII Code, •, , The ASCII stands for American Standard Code for Information Interchange. The ASCII code is an, alphanumeric code used for data communication in digital computers. The ASCII is a 7-bit code, capable of representing 27 or 128 number of different characters. The ASCII code is made up of a, three-bit group, which is followed by a four-bit code., , •, •, •, , The ASCII Code is a 7 or 8-bit alphanumeric code., This code can represent 127 unique characters., The 8-bit code holds ASCII, which supports 256 symbols where math and graphic symbols are, added., The ASCII characters are classified into the following groups:, , •

Page 41 : Indian Standard Code for Information Interchange (ISCII), •, , •, , ISCII–Indian Standard Code for Information Interchange(ISCII) is the system of handling the, character of Indian local languages. This is an 8-bit coding system. Therefore it can handle 256 (28), characters. It is recognized by the Bureau of Indian Standards (BIS). It is integrated with Unicode., 1. ISCII is a kind of coding scheme which is used to represent various writing systems of India., , •, , 2. It encodes the main Indiian scripts as well as Roman transliteration., , •, , 3. The scripts encoded by ISCII are: Assamese, Bengali, Devanagari, Gujarati, Gurmukhi, Kannada,, Malayalam, Oriya, Tamil, and TELUGU., , •, , 4. ISCII helps in using an 8-bit which is an extension of ASCII.

Page 42 : Unicode, •, , Unicode is a universal international standard character encoding that is capable of, representing most of the world's written languages., , •, , An international encoding standard for use with different languages and scripts, by, which each letter, digit, or symbol is assigned a unique numeric value that applies across, different platforms and programs., , •, , With Unicode each character uses a unique number between U+0000 and, U+10FFFF, Unicode may be 8-bit, 16-bit, or 32-bit. Numbers, mathematical notation,, popular symbols and characters from all languages are assigned a code point, for, example, U+0041 is an English letter "A." Below is an example of how "Computer Hope", would be written in English Unicode., U+0043 U+006F U+006D U+0070 U+0075 U+0074 U+0065 U+0072 U+00A0 U+0048, U+006F U+0070 U+0065, , •

Page 43 : Microprocessor, •, , A Microprocessor is an important part of a computer architecture without which you will not, be able to perform anything on your computer. It is a programmable device that takes input, performs some arithmetic and logical operations over it and produces the desired output. In simple, words, a Microprocessor is a digital device on a chip that can fetch instructions from memory,, decode and execute them and give results., , • Basics of Microprocessor –, A Microprocessor takes a bunch of instructions in machine language and executes them, telling the, processor what it has to do. Microprocessor performs three basic things while executing the, instruction:, 1. It performs some basic operations like addition, subtraction, multiplication, division, and some, logical operations using its Arithmetic and Logical Unit (ALU). New Microprocessors also perform, operations on floating-point numbers also., 2. Data in microprocessors can move from one location to another., 3. It has a Program Counter (PC) register that stores the address of the next instruction based on the, value of the PC, Microprocessor jumps from one location to another and takes decisions.

Page 45 : Types of Processor:, • Complex Instruction Set Computer(CISC) Processor, , •, •, •, •, •, •, •, •, •, , CISC or Complex Instruction Set Computer is a computer architecture where instructions, are such that a single instruction can execute multiple low-level operations like loading, from memory, storing into memory, or an arithmetic operation, etc. It has multiple, addressing nodes within a single instruction. CISC makes use of very few., registers. Example:, 1. Intel 386, 2. Intel 486, 3. Pentium, 4. Pentium Pro, 5. Pentium II, 6. Pentium III, 7. Motorola 68000, 8. Motorola 68020, 9. Motorola 68040 etc.

Page 46 : Reduced Instruction Set Computer (RISC), •, , Reduced Instruction Set Computer (RISC) –, RISC or Reduced Instruction Set Computer is a computer architecture where instruction is, simple and designed to get executed quickly. Instructions get completed in one clock, cycle this is because of the optimization of instructions and pipelining (a technique that, allows for simultaneous execution of parts, or stages, of instructions more efficiently, process instructions). RISC makes use of multiple registers to avoid large interactions with, , memory. It has few addressing nodes. Example:, •, , 1. IBM RS6000, , •, , 2. MC88100, , •, , 3. DEC Alpha 21064, , •, , 4. DEC Alpha 21164, , •, , 5. DEC Alpha 21264

Page 47 : Explicitly Parallel Instruction Computing (EPIC), •, , Explicitly Parallel Instruction Computing (EPIC) –, EPIC or Explicitly Parallel Instruction Computing permits computers to execute instructions, parallel using compilers. It allows complex instructions execution without using higher, , clock frequencies. EPIC encodes its instruction into 128-bit bundles. each bundle contains, three instructions which are encoded in 41 bits each and a 5-bit template field(contains, information about types of instructions in a bundle and which instructions can be, executed in parallel). Example:, •, , 1. IA-64 (Intel Architecture-64)

Page 48 : Classification of Memory

Page 49 : Computer Memory, •, , Computer memory is just like the human brain. It is used to store data/information and, instructions. It is a data storage unit or a data storage device where data is to be processed and, instructions required for processing are stored. It can store both the input and output can be, stored here., , Types of Computer Memory, 1. Primary memory, , 2. Secondary memory, 3. Cache memory, •, , 1. Primary Memory: It is also known as the main memory of the computer system. It is used to, store data and programs or instructions during computer operations. It uses semiconductor, , technology and hence is commonly called semiconductor memory. Primary memory is of two, types, •, , (i) RAM (Random Access Memory), , •, , (ii) ROM (Read Only Memory)

Page 50 : • (i) RAM (Random Access Memory):, •, •, •, •, , •, •, •, •, •, •, •, •, , It is a volatile memory. It means it does not store data, or instructions permanently. When you switch on the computer the data and instructions from the, hard disk are stored in RAM., CPU utilizes this data to perform the required tasks. As soon as you shut down the computer the, RAM loses all the data. RAM is of two types:, S RAM (Static RAM), D RAM (Dynamic RAM), SRAM: SRAM(Static Random-Access Memory) is a type of RAM used to store static data in the, memory. It means to store data in SRAM remains active as long as the computer system has a power, supply. However, data is lost in SRAM when power failures have occurred., Characteristics of Static Ram, It does not require to refresh., It is faster than DRAM, It is expensive., High power consumption, Longer life, Large size, Uses as a cache memory

Page 51 : •, , D RAM (Dynamic RAM): It uses capacitors and transistors and stores the data as a charge on, , the capacitors. They contain thousands of memory cells. It needs refreshing of charge on, capacitor after a few milliseconds. This memory is slower than S RAM., •, , Characteristics of DRAM, , •, , It requires continuously refreshed to retain the data., , •, , It is slower than SRAM, , •, , It holds a large amount of data, , •, , It is the combination of capacitor and transistor, , •, , It is less expensive as compared to SRAM, , •, , Less power consumption., , Read-Only Memory (ROM), ROM is a memory device or storage medium that is used to permanently store information inside a chip. It is a, read-only memory that can only read stored information, data or programs, but we cannot write or modify, anything. A ROM contains some important instructions or program data that are required to start or boot a, computer. It is a non-volatile memory; it means that the stored information cannot be lost even when the, power is turned off or the system is shut down.

Page 52 : Types of ROM(Read Only Memory), •, •, , •, , •, , •, , •, , There are five types of Read Only Memory, MROM (Masked Read Only Memory):, MROM is the oldest type of read-only memory whose program or data is pre-configured by the integrated, circuit manufacture at the time of manufacturing. Therefore, a program or instruction stored within the, MROM chip cannot be changed by the user., PROM (Programmable Read Only Memory):, It is a type of digital read-only memory, in which the user can write any type of information or program only, once. It means it is the empty PROM chip in which the user can write the desired content or program only, once using the special PROM programmer or PROM burner device; after that, the data or instruction cannot, be changed or erased., EPROM (Erasable and Programmable Read Only Memory):, It is the type of read only memory in which stored data can be erased and re-programmed only once in the, EPROM memory. It is a non-volatile memory chip that holds data when there is no power supply and can, also store data for a minimum of 10 to 20 years. In EPROM, if we want to erase any stored data and reprogrammed it, first, we need to pass the ultraviolet light for 40 minutes to erase the data; after that, the, data is re-created in EPROM., EEPROM (Electrically Erasable and Programmable Read Only Memory):, The EEROM is an electrically erasable and programmable read only memory used to erase stored data using, a high voltage electrical charge and re-programmed it. It is also a non-volatile memory whose data cannot, be erased or lost; even the power is turned off. In EEPROM, the stored data can be erased and, reprogrammed up to 10 thousand times, and the data erase one byte at a time., Flash ROM:, Flash memory is a non-volatile storage memory chip that can be written or programmed in small units called, Block or Sector. Flash Memory is an EEPROM form of computer memory, and the contents or data cannot be, lost when the power source is turned off. It is also used to transfer data between the computer and digital, devices.

Page 53 : Difference between RAM and ROM, RAM, , ROM, , It is a Random-Access Memory., , It is a Read Only Memory., , Read and write operations can be performed., , Only Read operation can be performed., , Data can be lost in volatile memory when the, power supply is turned off., , Data cannot be lost in non-volatile memory, when the power supply is turned off., , It is a faster and expensive memory., , It is a slower and less expensive memory., , Storage data requires to be refreshed in RAM., , Storage data does not need to be refreshed in, ROM., , The size of the chip is bigger than the ROM, chip to store the data., , The size of the chip is smaller than the RAM, chip to store the same amount of data., , Types of RAM: DRAM and SRAM, , Types of ROM: MROM, PROM, EPROM,, EEPROM

Page 54 : Cache Memory, •, •, , •, , Cache Memory, Cache memory is a high-speed memory, which is small in size but faster than the main, memory (RAM). The CPU can access it more quickly than the primary memory. So, it is, used to synchronize with high-speed CPU and to improve its performance., In other words, if the CPU finds the required data or instructions in the cache memory, it, doesn't need to access the primary memory (RAM). Thus, by acting as a buffer between, RAM and CPU, it speeds up the system performance.

Page 55 : Secondary Memory, •, , •, , The secondary storage devices which are built into the computer or connected to the, computer are known as a secondary memory of the computer. It is also known as, external memory or auxiliary storage., The secondary memory is accessed indirectly via input/output operations. It is nonvolatile, so permanently stores the data even when the computer is turned off or until, this data is overwritten or deleted. The CPU can't directly access the secondary memory., First, the secondary memory data is transferred to primary memory then the CPU can, access it., , Types of Secondary memory, Secondary memory is of two types:, 1. Fixed storage, 2. Removable storage, , • 1. Fixed storage, •, , In secondary memory, a fixed storage is an internal media device that is used to store data in a, computer system. Fixed storage is generally known as fixed disk drives or hard drives. Generally, the, data of the computer system is stored in a built-in fixed storage device. Fixed storage does not mean, that you can not remove them from the computer system, you can remove the fixed storage device, for repairing, for the upgrade, or for maintenance, etc. with the help of an expert or engineer.

Page 56 : •, •, •, •, •, •, , •, •, •, •, •, •, •, , Following are the types of fixed storage:, Internal flash memory (rare), SSD (solid-state disk), Hard disk drives (HDD), 2. Removable storage, In secondary memory, removable storage is an external media device that is used to, store data in a computer system. Removable storage is generally known as disks drives, or external drives. It is a storage device that can be inserted or removed from the, computer according to our requirements. We can easily remove them from the, computer system while the computer system is running. Removable storage devices are, portable so we can easily transfer data from one computer to another. Also, removable, storage devices provide the fast data transfer rates associated with storage area, networks (SANs)., Types of Removable Storage:, Optical discs (like CDs, DVDs, Blu-ray discs, etc.), Memory cards, Floppy disks, Magnetic tapes, Disk packs, Paper storage (like punched tapes, punched cards, etc.)

Page 57 : Secondary memory devices, •, •, , •, , •, , •, •, , Following are the commonly used secondary memory devices are:1. Floppy Disk: A floppy disk consists of a magnetic disc in a square plastic case. It is, used to store data and to transfer data from one device to another device. Floppy disks, are available in two sizes (a) Size: 3.5 inches, the Storage capacity of 1.44 MB (b) Size:, 5.25 inches, the Storage capacity of 1.2 MB. To use a floppy disk, our computer needs, to have a floppy disk drive. This storage device becomes obsolete now and has been, replaced by CDs, DVDs, and flash drives., 2. Compact Disc: A Compact Disc (CD) is a commonly used secondary storage device. It, contains tracks and sectors on its surface. Its shape is circular and is made up of, polycarbonate plastic. The storage capacity of CD is up to 700 MB of data. A CD may, also be called a CD-ROM (Compact Disc Read-Only Memory), in this computers can read, the data present in a CD-ROM, but cannot write new data onto it. For a CD-ROM, we, require a CD-ROM. CD is of two types:, CD-R (compact disc recordable): Once the data has been written onto it can not be, erased, it can only be read., CD-RW (compact disc rewritable): It is a special type of CD in which data can be erased, and rewritten as many times as we want. It is also called an erasable CD.

Page 58 : •, , 3. Digital Versatile Disc: A Digital Versatile Disc also known as DVD it is looks just like a CD, but, , the storage capacity is greater compared to CD, it stores up to 4.7 GB of data. DVD-ROM drive, is needed to use DVD on a computer. The video files, like movies or video recordings, etc., are, generally stored on DVD and you can run DVD using the DVD player. DVD is of three types:, •, , DVD-ROM(Digital Versatile Disc Read only): In DVD-ROM the manufacturer writes the data in, it and the user can only read that data, cannot write new data in it. For example movie DVD,, movie DVD is already written by the manufacturer we can only watch the movie but we, cannot write new data into it., , •, , DVD-R(Digital Versatile Disc Recordable): In DVD-R you can write the data but only one time., Once the data has been written onto it cannot be erased, it can only be read., , •, , DVD-RW(Digital Versatile Disc Rewritable and Erasable): It is a special type of DVD in which, data can be erased and rewritten as many times as we want. It is also called an erasable DVD., , •, , 4. Blu-ray Disc: A Blu-ray disc looks just like a CD or a DVD but it can store data or, information up to 25 GB data. If you want to use a Blu-ray disc, you need a Blu-ray reader. The, name Blu-ray is derived from the technology that is used to read the disc ‘Blu’ from the blueviolet laser and ‘ray’ from an optical ray.

Page 59 : •, , 5. Hard Disk: A hard disk is a part of a unit called a hard disk drive. It is used to storing a, large amount of data. Hard disks or hard disk drives come in different storage, capacities.(like 256 GB, 500 GB, 1 TB, and 2 TB, etc.), , •, , Hard disk is of two types:- (i) Internal hard disk, , •, , 6. Flash Drive: A flash drive or pen drive comes in various storage capacities, such as 1, , (ii) External hard disk., , GB, 2 GB, 4 GB, 8 GB, 16 GB, 32 GB, 64 GB, up to 1 TB. A flash drive is used to transfer, and store data. To use a flash drive, we need to plug it into a USB port on a computer., As a flash drive is easy to use and compact in size, Nowadays it is very popular., •, , 7. Solid-state disk: It is also known as SDD. It is a non-volatile storage device that is, used to store and access data. It is faster, does noiseless operations(because it does not, contain any moving parts like the hard disk), consumes less power, etc. It is a great, replacement for standard hard drives in computers and laptops if the price is low and it, is also suitable for tablets, notebooks, etc because they do not require large storage.

Page 60 : •, , 6. Flash Drive: A flash drive or pen drive comes in various storage capacities, such as 1, , GB, 2 GB, 4 GB, 8 GB, 16 GB, 32 GB, 64 GB, up to 1 TB. A flash drive is used to transfer and, store data. To use a flash drive, we need to plug it into a USB port on a computer. As a, flash drive is easy to use and compact in size, Nowadays it is very popular., , •, , 7. Solid-state disk: It is also known as SDD. It is a non-volatile storage device that is used, to store and access data. It is faster, does noiseless operations(because it does not, contain any moving parts like the hard disk), consumes less power, etc. It is a great, replacement for standard hard drives in computers and laptops if the price is low and it is, also suitable for tablets, notebooks, etc because they do not require large storage.

Page 61 : Memory Units, •, •, , •, •, •, •, •, •, •, •, •, •, •, •, •, •, , Memory units are used to measure and represent data. Some of the commonly used memory units, are:, 1) Bit: The computer memory units start from bit. A bit is the smallest memory unit to measure data, stored in main memory and storage devices. A bit can have only one binary value out of 0 and 1., 2) Byte: It is the fundamental unit to measure data. It contains 8 bits or is equal to 8 bits. Thus a byte, can represent 2*8 or 256 values., Bit = 0 or 1, 4 Bit = 1 Nibble, 2 Nibble and 8 Bit = 1 Byte, 1024 Byte = 1 KB (Kilo Byte), 1024 KB = 1 MB (Mega Byte), 1024 MB = 1 GB (Giga Byte), 1024 GB = 1 TB (Tera Byte), 1024 TB = 1 PB (Penta Byte), 1024 PB = 1 EB (Exa Byte), 1024 EB = 1 ZB (Zetta Byte), 1024 ZB = 1 YB (Yotta Byte), 1024 YB = 1 BB (Bronto Byte), 1024 BB = 1 GB (Geop Byte)

Page 62 : Input Output Ports, •, •, •, •, •, , Input Output Ports, Ports: The connection point acts as an interface between the computer and external, devices like printers, modems, etc., There are two types of ports :Internal Port:- It connects the system’s motherboard to internal devices like hard disk, CD, drive, internal Bluetooth, etc., External Port:- It connects the system’s motherboard to external devices like a mouse,, printer, USB, etc., , •, •, •, •, , 1. Serial Port:, Used for external modems and older computer mouse, Two versions-9pin,25pin, Data travels at 115 kilobits per second, , •, , This type of ports provides an interface to connect to peripheral devices using a serial, protocol.

Page 63 : • 2. Parallel Port :, •, •, •, , Used for scanners and printers, 25 pin model., A Parallel port is an interface that allows communication or data transfer between a, computer and a device in a parallel manner through more than one communication line., For example, a printer port is a parallel port., , • 3. Universal Serial Bus (or USB) Port :, •, •, •, , •, •, , It can connect all kinds of external USB devices such as external hard disks, printers, scanners, mouse,, keyboards, etc., Data travels at 12 megabits per second., USB(Universal Serial Bus) port is very versatile in use; It can be used for various purposes, such as to, transfer data, to connect peripheral devices, and even as an interface for charging devices such as, smartphones, digital cameras, etc. Today, it has replaced PS/2 connectors, game ports, serial and, parallel ports, etc., USB Type A:USB Type C:-

Page 64 : • 4. Firewire Port :, •, •, •, •, , Transfers large amounts of data at a very fast speed., Connects camcorders and video equipment to the computer., Data travels at 400 to 800 megabits per second., Firewire was one of the connectors used in digital devices especially in printers and, digital Cameras. It was introduced by Apple. It came with some extraordinary features, that the other connectors doesn’t provide at that time., , •, •, , 5. Infrared Port:, An Infrared(IR) port is used to sends and receives infrared signals from other devices. It is, a kind of wireless type port with a limited range of 5-10ft.

Page 65 : Bluetooth Port, •, , It is basically a telecommunication port that allows wireless connection and exchange of, data over a short-range wireless connection. Moreover, it is possible in mobiles,, computers and other digital devices too. Besides, it uses short-range radio waves for, sharing the data. The range for Bluetooth connection is around 10m., , •, , it is commonly used in PC s, mobiles, wireless, keyboards, wireless speakers are using, Bluetooth effectively., , •, , There are two types of Bluetooth ports as follows:, , •, , Incoming Port: It receives connections from other Bluetooth devices., , •, , Outgoing Port: It requests connection to other Bluetooth devices.