Introduction

C is a mid-level structured oriented programming language, used in general-purpose programming, developed by Dennis Ritchie at AT&T Bell Labs, the USA, between 1969 and 1973.

Why Learn C?

It is one of the most popular programming language in the world.
If you know C, you will have no problem to learn other popular programming languages such as Java, Python, C++, C#, etc, as the syntax is similar.
C is very fast, compared to other programming languages, like Java and Python.
C is very versatile; it can be used in both applications and technologies.

Difference between C and C++

C++ was developed as an extension of C, and both languages have almost the same syntax.
The main diffference between C and C++ is that C++ support classes and objects, while C does not.

Get Started with C

To start using C, you need two things:

A text editor, like Notepad, to write C code
A compiler, like GCC, to translate the C code into a language that the computer will understand

There are many text editors and compilers to choose from. In this tutorial, we will use an IDE (see below).

C Install IDE

An IDE (Integrated Development Environment) is used to edit AND compile the code.

Popular IDE's include Code::Blocks, Eclipse, and Visual Studio. These are all free, and they can be used to both edit and debug C code.

Note: Web-based IDE's can work as well, but functionality is limited.

We will use Code::Blocks in our tutorial, which we believe is a good place to start.

You can find the latest version of Codeblocks at http://www.codeblocks.org/downloads/26. Download the mingw-setup.exe file, which will install the text editor with a compiler.

C Quickstart

Let's create our first C file.

Open Codeblocks and go to File > New > Empty File (File > Save File as):
Write the following C code and save the file as:

myfirstprogram.c

Comments in C

Comments can be used to explain code, and to make it more readable. It can also be used to prevent execution when testing alternative code. Comments can be singled-lined or multi-lined.

Single-line Comments

Single-line comments start with two forward slashes //.

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// This is a comment printf ("Hello World!");

This example uses a single-line comment at the end of a line of code:

C Multi-line Comments Multi-line comments

/* This is code This is code */

/* The code below will print the words Hello World!
to the screen, and it is amazing */
printf ("Hello World!");

Data Types

As explained in the Variables chapter, a variable in C must be a specified data type, and you must use a format specifier inside the printf()

Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.

Variables