Understanding the Problem:

A variable in C is a storage location, identified by a name (identifier), used to store data that can be modified during program execution. It is essentially a container for storing values. The type of variable defines what kind of data it can hold, such as integers, floating-point numbers, or characters.

Code Implementation:

 
int number = 5;
float decimal = 3.14;
char letter = 'A';

Code Explanation:

• In the above code, int number = 5; declares an integer variable named number and initializes it with the value 5. The data type int signifies that the variable can hold integer values.
• float decimal = 3.14; declares a floating-point variable decimal and initializes it with 3.14. The data type float allows the variable to store decimal values.
• char letter = 'A'; declares a character variable named letter and assigns it the value 'A'. The data type char stores a single character.

Variables in C must be declared before use, specifying the type of data they will hold. They can be initialized at the time of declaration or later in the program.