What is int ?

Answer 1

Int is short for "integer." Int is a fundamental variable type built into the compiler and used to define numeric variables holding whole numbers. C, C++, C# and many other programming languages recognize int as a type.
such as

#include <iostream>
using namespace std;

int main()
{
int a = 30;
int b = 12;
int sum = a + b;

cout << sum;

return 0;
}

Answer 2

int is short for integer

1 is an int
2 is an int
23 is an int

to research :
it is that number which in binary is stored without much ado i.e. it is stored as it is, compare to float storage