What is the difference between declaring a variable and defining a variable?

Understanding Variable Declaration vs. Variable Definition in Programming

Declaring a variable means describing its type to the compiler but not allocating any space for it. Defining a variable means declaring it and also allocating space to hold the variable. You can also initialize a variable at the time it is defined.

Declaring a variable and defining a variable are two different concepts in programming.

Declaring a variable means telling the compiler about the existence of a variable without allocating memory space for it. It provides the name and data type of the variable to the compiler, but does not assign any value to it. A variable can be declared using the syntax:

data_type variable_name;

Defining a variable means both declaring a variable and allocating memory space for it. It provides the name, data type, and an initial value for the variable. A variable can be defined using the

syntax:

data_type variable_name = value;

In summary, declaring a variable means announcing the variable to the compiler, while defining a variable means announcing and allocating memory space for it.