1. 1. INTRODUCING C

2. History of C
• Designed and implemented by Dennis Ritchie of Bell Labs between 1969 and 1973.
• Created to serve as the implementation language for the UNIX operating system.
• Named after the B language, its immediate predecessor (which in turn was named after the BCPL language).
• Became popular during the 1980s, both for UNIX programming and for developing applications for personal computers.
• Dennis Ritchie’s article, “The Development of the C Language,” can be found on the web at
cm.bell-labs.com/cm/cs/who/dmr/chist.html.

3. Versions of C
• K&R C
Described in Kernighan and Ritchie, The C Programming Language, Prentice-Hall, 1978
• ANSI C (ISO C, C89)
ANSI standard X (completed in 1988; formally approved in December 1989)
International standard ISO/IEC 9899:1990
Described in Kernighan and Ritchie, The C Programming Language, Second Edition, Prentice-Hall, 1988
• C99
International standard ISO/IEC 9899:1999

4. Advantages of C • Advantages Efficient Portable Powerful Flexible
Standard library
Integrated well with UNIX

5. Disadvantages of C • Disadvantages Error-prone Difficult to understand
Difficult to maintain

6. Recommendations • Recommendations
Use tools (lint, debuggers, etc.) to make programs more reliable.
Use libraries of existing code (both to save time and increase reliability).
Adopt a sensible set of coding conventions.
Avoid “tricks” and complicated code.