Hardware and Software.pdf
- 1. Hardware and Software Hardware:- All the physical part of the computer which we can see and touch them, and wherever thy do not work properly then we can change it those types of equipments are called hardware. Eg. CPU, Mouse, keyboard, printer, Monitor, Scanner, Ram, BUS. Hardware can be classified as: Hardware C.P.U. Peripherals Control Unit Memory Input devices Output devices ALU Primary Secondary (Arithmetic Logic Unit) Software: A set of progress associated with the operation of a computer is called software” Or “A Collection of programs called software or software programs” These programs must reside in the internal storage (memory) to execute their instructions. For Example if we want to delete some data stored in memory the system uses one set of program instructions. Similary’s , if we want to sort a list of name, it uses another set of instruction designed to perform this task. Software can be classified into the following major categories: 1. System Software eg. O.S. 2. Application software eg. Word processors, Spreadsheet, DBMS 3. Language Processors.
- 2. 4. Utility programs. eg win zip, antivirus, Acrobat reader 5. Other application programs doing a specific job: Eg. Accounting, billing, ticket reservation etc 1. System Software: A system software is also a group of computer programs that run a computer system it self concerned primarily with coordinating and controlling hardware and communications resources rather than application task. Eg. Any operating system, DOS,, Windows 95, UNIX, Linux, Windows NT Novell L etc. 2. Application software: “ set of the program written to perform specific task word processing (MS word) Spread Sheets ( Lotus 123, MS Excel) Date base ( D Base, oracle. ) Presentation (MS PowerPoint, Linear Program 3. Language Processors: /Translators Computer can understand instructions only when they are written in their own language called the machine language. Therefore, a program written in any other language should be translated into machine language. Special programs called language processors are available to do this job. These special programs accept the users programs and cheek each statement and, if it is grammatically correct, produce a corresponding set of machine code instructions language processors are also known as translators. Translators are two types: 1. Compilers Whole at a time 2. Interpreters one by one 1. Compiler : A Complier cheek the entire user written program ( known as the source program and, it error- free, produces a complete program in machine language (known as object program). The source program is retained for possible modifications and corrections and the object program is loaded into the computer for execution. 2. Interpreters : An interpreter does a similar job but in a different style. The interpreter (as name implies) translates one statement at a time and if error, free, executes. This continues till the least statement Thus an interpreter translates and executes the first instruction before it goes to the second, while complier translates the whole program before execution.
- 3. The major difference between them are: 1. Error correction (called debugging) is much simpler in the case of the interpreter because it is done in stage. The complier produces an error list for the entire program at the end. 2. Interpreters take more time for the execution 5b a program compared to compilers because a statement has to be translated every time it is read. Note: compilers and interpreters are usually written and supplied by the vendors. Since a complier (or an interpreter) can translate only a particular language for which it is designed, one will need to use a separate translator for each language. 3. Utility Programs: A computer program the supports operating system by providing the additional services that the operating system does not provides. Eg. Win zip : to reduce the file size Antivirus: to protect the computer from virus acrobat reader: to read pdf files.