C Programming language Tutorial

C is a widely used procedural and general-purpose programming language for system programming. Dennis Ritchie initially developed C between 1972 and 1973 at Bell Labs. American National Standard Institute (ANSI) later formalized this programming language in 1988. The initial purpose of developing the C programming language was to make utilities of the UNIX-based operating system. Many other computer programming languages have directly or indirectly taken/borrowed features from the C programming language. Program written in C can be very efficiently mapped to machine instructions, making C programming very popular for any embedded software application development that runs on a microcontroller.

Why do we need to learn C?

C is the most widely and commonly used programming language to develop different operating systems. Popular operating systems like UNIX and LINUX are written in C.
C program allows programs to maintain portable and compact code while maintaining performance and minimizing CPU constraints like memory, execution time, etc.
C programming language allows programmers to control memory allocation and reallocation, which will be very helpful while working with software development for small embedded systems.
C is a middle-level language and very fast in execution compared to other programming languages.
Different algorithms and data structures can be implemented using the C language very efficiently, which can be used in many software applications.
Due to the portability feature of the C programming language, the C program written for one computer platform can easily be run on different other platforms with very little modification in code.
Various compilers used for other programming languages can be very efficiently designed and developed using the C programming language.

Applications of C

To develop and design system software like compilers for other programming languages.
To develop different operating systems for embedded devices and kernels.
To develop graphics-related software like gaming applications.
To design and develop network device software.
To develop a software system where memory and execution time are constrained like microcontrollers software, mainly used for small embedded systems.
Used for systems that require direct access/modification of data from memory.

Example (One short example)

To understand the C programming language, look at the below sample example code, where two age variables are taken as input and compared for age comparison.

Code:

#include <stdio.h> int main() { int age1 = 100; int age2 = 80; if (age1 > age2) { printf("age1 is greater than age 2"); } else { printf("age2 is greater than age 1"); } return 0; }

Output:

Prerequisites

It would help to understand computer programming language methodologies like variables, conditions, looping, constants, operators, etc. Knowledge of any other programming language is an added advantage to learning this tutorial.

Target Audience

This tutorial is designed for software programmers who wish to understand the C programming language and apply C programming in their projects.