Computer Basics

You know that low-level language requires extensive knowledge of the hardware since it is machine-dependent. To overcome the limitation, high-level language has evolved which uses normal English-like, easy-to-understand statements to solve any problem. Higher-level languages are computer-independent and programming becomes quite easy and simple. 1. BASIC (Beginners All Purpose Symbolic Instruction Code): It is a widely used, easy-to-learn general-purpose language. Mainly used in microcomputers in earlier days. 2. COBOL (Common Business Oriented Language): A standardized language used for commercial applications. 3. FORTRAN (Formula Translation): Developed for solving mathematical and scientific problems. One of the most popular languages in the scientific community. 4. C: Structured Programming Language used for all purposes such as scientific application, commercial application, developing games, etc. 5. C++: Popular object-oriented programming language, used for general purposes.

The term low level means closeness to the way in which machines understand. The low-level languages are: 1. Machine Language: This is the language (in the form of 0’s and 1’s, called binary numbers) understood directly by the computer. It is machine-dependent. It is difficult to learn and even more difficult to write programs. 2. Assembly Language: This is the language where the machine codes comprising of 0’s and 1’s are substituted by symbolic codes (called mnemonics) to improve their understanding. It is the first step to improving the programming structure.

Languages are a means of communication. Normally people interact with each other through a language. In the same pattern, communication with computers is carried out through a language. This language is understood both by the user and the machine. Just as every language like English, Hindi has its grammatical rules; every computer language is bound by rules known as SYNTAX of that language. The user is bound by that syntax while communicating with the computer system.

These are the applications that are customized (or developed) to meet the specific requirements of an organization/institution. For Example Student information details, Payroll packages, inventory control, etc. These packages are developed using a high-level computer language.

These are user-friendly software written to cater to users’ very general needs such as preparing documents, drawing pictures, databases to manage data/information, preparing presentations, playing games, etc. 1. Word Processing Software(for preparing documents): Word Perfect, MS-Word, OpenOffice.org Writer 2. Spreadsheets (Data Analysis): Lotus Smart suites, MSExcel, OpenOffice.org Calc, Apple Numbers 3. Presentations: Presentation Graphics, MS PowerPoint, OpenOffice.org Impress 4. Database Management System: MS-Access, OpenOffice.org Base, MS-SQL Server, ORACLE 5. Graphics Tools: Paint shop pro, Adobe Photoshop

Application software is a set of programs, which are written to perform specific tasks. Application software can be into two types: 1. Generalized packages 2. Customized packages

When you switch on the computer the programs stored in ROM are executed which activates different units of your computer and makes it ready for you to work on it. This set of programs can be called system software. The operating system is system software that provides an interface for a user to communicate with the computer, manages hardware devices manages and maintains disk file systems, and supports application programs. Some popular Operating systems are UNIX, Windows, and Linux.

The computer cannot do anything on its own. It is the user who instructs the computer; on what to do, how to do and when to do it. In order to perform any task, you have to give a set of instructions in a particular sequence to the computer. These sets of instructions are called Programs.

Speakers are another type of output device, which allow you to listen to voice-like music and conversation with people.

After a document is created on the computer, it can be sent to a printer for a hard copy. Some printers offer special features such as colored and large page formats. Some of the most commonly used printers are: 1. Laser Printer 2. Ink Jet Printer 3. Dot Matrix Printer 4. Line Printer

The monitor is perhaps the most important output device because people interact with this device most intensively than others. Two basic types of monitors are used with microcomputers, which are as follows: 1. Cathode Ray Tube (CRT): CRT or Cathode Ray Tube Monitor is the typical monitor that you see on a desktop computer. It looks a lot like a television screen and works the same way. This type uses a large vacuum tube, called a cathode ray tube (CRT). 2. Liquid Crystal Displays (LCD): This type of monitor is also known as a flat panel monitor. Most of these employ liquid crystal displays (LCDs) to render images. These days LCD monitors are very popular.

Output devices return processed data that is information, back to the user. Some of the commonly used output devices are: 1. Monitor (Visual Display Unit) 2. Printers 3. Plotter 4. Speakers

A trackball, a pointing device, is a mouse lying on its back. To move the pointer, you rotate the ball with your thumb, your fingers, or the palm of your hand. There are usually one to three buttons next to the ball, which you use just like mouse buttons.

The microphone is an input device, which takes voice as input. Voice communication is more error-prone than information through the keyboard. There are two types of microphones available. 1. Desktop Microphone 2. Handheld Microphone

Touch panel displays and pads are now being offered as alternatives to keyboards. Here the input can be given through the computer screen, which accepts the input through the monitor; users touch electronic buttons displayed on the screen or they may use the light pen.

These devices are used for automatic data collection. The devices of this category completely eliminate manual input of data. For example, the bar-code reader is actually just a special type of image scanner.

An input device that utilizes a light-sensitive detector to select objects on a display screen. A light pen is similar to a mouse.

A mouse is an electro-mechanical, hand-held device. It is used as a pointer. It can perform functions like selecting menu commands, moving icons, resizing windows, starting programs, and choosing options.

A keyboard is the most common input device.

Input devices accept data and instructions from the user. Following are examples of various input devices, which are connected to the computer for this purpose.

The computer is a device that transforms data into meaningful information. A computer can :- 1. Accept data, 2. Store data, 3. Process data as desired, 4. Retrieve the stored data as and when required, 5. Print the result in the desired format.

The computer performs computer five major operations. These are:- 1. Input 2. Control Unit (CU) 3. Memory Unit 4. Arithmetic Logic Unit (ALU) 5. Output

A computer is a digital electronic machine that can be programmed to carry out sequences of arithmetic or logical operations (computation) automatically. A computer is a digital electronic machine that can be programmed to carry out sequences of arithmetic or logical operations (computation) automatically.