INTRODUCION TO C PROGRAMMING

Introduction

C is a general-purpose high level language that was originally developed by Dennis Ritchie for the Unix operating system. It was first implemented on the Digital Eqquipment Corporation PDP-11 computer in 1972.

The Unix operating system and virtually all Unix applications are written in the C language. C has now become a widely used professional language for various reasons.

  • Easy to learn
  • Structured language
  • It produces efficient programs.
  • It can handle low-level activities.
  • It can be compiled on a variety of computers.

Why to use C

C was initially used for system development work, in particular the programs that make-up the operating system. C was adoped as a system development language because it produces code that runs nearly as fast as code written in assembly language. Some examples of the use of C might be:

  • Operating Systems
  • Language Compilers
  • Assemblers
  • Text Editors
  • Print Spoolers
  • Network Drivers
  • Modern Programs
  • Data Bases
  • Language Interpreters
  • Utilities

C Program File

A source code file is a human readable text file that contains a collection of statements or declarations in any of many computer programming languages (e.g. BASIC, PASCAL, DELPHI, C, C++, C#, COBOL, etc.). Source code is the mechanism used by programmers and developers to specify the actions to be performed by the computer.

A C program can vary from 3 lines to millions of lines and it should be written into one or more text files with extension “.c”; for example, hello.c. You can use “vi”, “vim” or any other text editor to write your C program into a file.

Structure Of C

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