introduction to c

1. INTRODUCTION
CHAPTER 1

3. C is a general-purpose programming language that
was developed in 1972 by Dennis Ritchie at Bell Labs.
The development of C was closely tied to the
development of the Unix operating system, which was
being created at Bell Labs at the time.

4. HISTORY OF C

5. The origins of C can be traced back to the mid-1960s,
when Martin Richards developed a high-level
computer language called BCPL (Basic Combined
Programming Language). BCPL was intended to be
used for writing operating systems, and many of the
concepts that were later inherited by C, such as arrays,
were first developed in BCPL.

6. In the late 1960s, Ken Thompson, who was also
working at Bell Labs, developed a new version of BCPL
called B. B was a significant improvement over BCPL,
but was still considered to be a "mid-level" language,
as it did not provide many of the features that are now
considered to be standard in modern programming
languages.

7. In the early 1970s, Dennis Ritchie began working on a
new version of B, which he intended to be a more
powerful and efficient language. He named this new
language C, as it was a significant improvement over B.

8. C was first used for the development of the Unix
operating system, and quickly became popular among
Unix programmers. In 1978, Brian Kernighan and
Dennis Ritchie published "The C Programming
Language", which became known as the "C Bible" and
helped to spread the use of C to other systems and
applications.

9. INTRODUCTION TO C

10. C is a general-purpose, high-level programming
language that was first developed by Dennis Ritchie in
the early 1970s. It was designed to be a portable,
efficient, and flexible language that could be used for a
wide range of purposes, from system programming to
application development. C is known for its low-level
access to memory and its ability to handle multiple
tasks at once, making it a popular choice for operating
systems, embedded systems, and other performance-
critical applications.

11. C is a high-level programming language that
resembles algebraic expressions and has features for
lower-level systems programming and applications
programming. It contains keywords such as "if", "else",
"for", "do", and "while". It bridges the gap between
machine language and conventional high-level
languages, allowing it to be used for both systems
programming (e.g. operating systems) and
applications programming (e.g. mathematical
equations or billing customers).

12. It is also widely used in the development of other
programming languages and tools. Despite its age, C
remains a widely-used and powerful programming
language, with a large and active community of
developers around the world.

13. C is considered a procedural programming language. It
is based on the concept of procedures or functions,
which are executed sequentially. A C program is
typically divided into functions, which are blocks of
code that perform a specific task. These functions are
called one after the other to accomplish the overall
program. In procedural programming, the program is
composed of a series of procedures, and the flow of
control is determined by calling these procedures in a
specific order.

14. IMPORTANT OF PROGRAM

15. Widely used: C is one of the most widely used programming
languages in the world, and it is the foundation of many other
programming languages and tools.
Systems programming: C also has features for lower-level language
and gives the programmer a lot of control over memory management
and system resources. This makes it well-suited for tasks such as
operating system development, device drivers, and other systems-
level programming.
Portability: C is designed to be portable, meaning that it can be easily
adapted to different hardware and operating systems. This makes it a
great choice for cross-platform development.
Performance: C is a compiled language, which means that it is
translated into machine code before it is executed. This makes it a
very efficient language, with relatively fast execution times.

16. Large Community: C has a large community of developers around the
world, which means that there are many resources available for
learning and troubleshooting.
Embedded systems: C is widely used in embedded systems
development, which include microcontrollers, embedded Linux and
other types of systems that require low-level control and
optimization.
Legacy systems: Many existing software systems are written in C, and
they are still in use today. Therefore, knowledge of C is important for
maintaining and updating these systems.
C's simplicity: C has a relatively simple and straightforward syntax
which makes it easy to learn and understand, and it is also relatively
easy to debug.

17. DESIRED PROGRAM CHARACTERISTICS

18. Characterstic Description
Integrity The accuracy of the calculations is of utmost
importance and should be maintained at all times. All
other program enhancements are meaningless if the
calculations are not carried out correctly.
Clarity Clarity in programming refers to the ease of
understanding the code, logic, and structure. A clear
program is readable, well-organized, and follows a
consistent structure, making it easier for other
programmers to understand and for the original
author to maintain. The design of the C programming
language emphasizes clear and readable code
through a disciplined approach to programming.

19. Characterstic Description
Simplicity Simplicity is an important principle in programming.
A simple program is easier to understand, maintain,
and debug, leading to better clarity and accuracy.
Sometimes, it may be necessary to trade off some
computational efficiency for simplicity in the
program structure. This can result in a clearer, more
straightforward program.
Efficiency Efficiency refers to the speed and memory usage of a
program. While these are important goals, they
should not compromise clarity and simplicity.
Balancing the tradeoff between efficiency, clarity,
and simplicity often requires experience and good
judgement.

20. Characterstic Description
Modularity Modular programming involves dividing a program
into smaller, independent modules or functions that
each perform a specific subtask. This enhances the
accuracy, clarity, and organization of the program,
and makes it easier to maintain and modify in the
future. In C, these modules are implemented as
functions. Modular programming leads to improved
structure and readability of a program.
Generality Generality in programming refers to the ability of a
program to handle a wide range of inputs and
situations, rather than being limited to a specific set
of fixed values. A program that is designed to be
general is more flexible, reusable, and adaptable to
changing requirements. The objective is to create a
program that can be used in many different contexts,

21. with a minimum of modification. With relatively little
effort, a program can often be made quite general,
enhancing its value and utility.

22. FUN FACT
NASA STILL OPERATES SOME PROJECTS ON
PROGRAMMING FROM THE 1970’S