What is variable?

Answer 1

It is a named memory location.
You can understand this even more easily by imaging a memory space, so whenever you want to create a space for some data of any data type, you basically assign a variable(name) to that memory location for being able to access it with the same variable name whenever you need it.

int a =5;
Here you telling the compiler to store 5 which is of int datatype in the memory location which you are naming a.