Variables in C Programming Language

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Variables in C :

A variable is a name for an area in memory.
The name of a variable (also called the identifier) must begin with either a letter or an underscore and can be composed of letters, digits, and the underscore character.
Variable naming conventions differ, however using lowercase letters with an underscore to separate words is common (snake_case).
Variables must also be declared as a data type before they are used.

The value for a declared variable is changed with an assignment statement.

For example, the following statements declare an integer variable my_var and then assigns it the value 42:

int my_var;
my_var = 42;

You can also declare and initialize (assign an initial value) a variable in a single statement:

int my_var = 42;

Let's define variables of different types, do a simple math operation, and output the results:

#include <stdio.h>

int main()
{
    int a, b;
    float salary = 56.23;
    char letter = 'Z';
    a = 8;
    b = 34;
    int c = a+b;
    printf("%d \n", c);
    printf("%f \n", salary);
    printf("%c \n", letter);
    return 0;
}

As you can see, you can declare multiple variables on a single line by separating them with a comma. Also, notice the use of format specifiers for float (%f) and char (%c) output.

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