Programming : Introduction

For computer hardware to perform a useful task it must be given a set of instructions to tell it what to do. A program is a sequence of instructions which tells the hardware how to carry out a particular job.

New programs are usually only created if there is no existing software package that will perform the same job. Writing a program involves a lot of work so if you can carry out a task with an off-the-shelf package such as a database you will probably find it much easier and cheaper to use the existing package. Developing a sophisticated computer program may take many thousands or even tens of thousands of man hours.

Because developing a program is a complicated task it is important that the program is planned properly before it is written. Programmers usually follow the systems life cycle when developing a program. Tools such as flowcharts are used to plan how a program will operate. The programs that you use such as computer games, utilities and desktop publishers were all created with a programming language.

There are different levels of programming language. Most computer programs are written in a high level language but for some tasks a low level language must be used.

GCSE ICT Companion 04 - (C) P Meakin 2004