It is different from decimals (called floating point numbers in computers). For example, 5.8 is a decimal, not an integer.

Variables, that is, they can be changed, such as int I；;

I is a variable, you can assign it i=2, i=3 and so on.

It is different from a constant, such as 5. It is a constant and cannot be assigned, such as 5 = 6, which is unacceptable.

An integer variable is a variable that can be assigned an integer value.