Hello World in C
So Guys,
To start with C, you need a machine and a C compiler. A Compiler is a program that converts your C code into machine's language so that machine can understand it and run it. If you have both, you are ready to get started.
But first you would like to get a brief introduction about C language.
According to what my sir has told us, Bell Labs (somewhere in USA) first developed a language called Basic Computer Programming Language(BCPL). Then a man in Bell labs further shortened the commands(instructions) it and named the resulting language just B. After that, Dennis Ritchie, too from Bell Labs. modified the code to consume much less memory. And he named it C. This is the history of C language. Now lets get started!

Below is the program that prints "Hello World!" on the monitor!

#include<stdio.h>
void main()
{
     printf("Hello World!");
}

Explanation:-

#include<stdio.h> - It says which files to be included in the program. The C program needs some Header Files (.h) to be included in the program. Header files are where the commands or instructions are defined
e.g. 'printf' is defined in 'stdio.h'
Likewise different commands are stored in different header files.
Most commonly needed header files are 'stdio.h' , 'conio.h', 'math.h', 'graphics.h' etc.

Syntax :- #include<nameof the file>
Note :- #include is always used at the start of the program

void main() - This is where your real program starts ... main(). "void" before main indicates it returns nothing. You must be wondering what does return a value means? Take an example, what do you get after "2+3"? you get "5". So 5 is the value that is returned. What will you answer if anybody asks "What is the name of your planet?". "Earth" is what you return(unless you are some alien). Just like this, when you ask program to do something, it returns some value. If it returns nothing then it returns "void". In the above program we are not asking the compiler anything, we are ordering it to print "Hello World!". So it doesnt answer us anything, just obeys the order quietly. It returns nothing, hence void.
A function can normally return integer,float,character,pointer etc. You will come to know about it later.

{ - This bracket signifies the start of a function or program.

printf("Hello World"); - This command performs(orders the compiler) to do what we want - Display "Hello World!" on monitor screen! printf is a standard library function. A semicolon after every command is necessary in C.

Syntax :- printf("the string you want to print");

} - This bracket signifies the end of the function or program.

So you wrote the program now! Now comes the main part! Run it you Idiot!
Compiling and running a program depends on what Compiler you are using. In UNIX or LINUX, you can compile C programs by "gcc filename" command in the commandline or terminal. For most of the other just hit Ctrl+F9 to run it. Read your compiler manual for more help.