int, short, long, signed and unsigned

The int keyword is used to declare integer type variables. For example:

int count;

Here, count is an integer variable.

short, long, signed and unsigned

The short, long, signed and unsigned keywords are type modifiers that alter the meaning of a base data type to yield a new type.

short int smallInteger;
long int bigInteger;
signed int normalInteger;
unsigned int positiveInteger;

Data types	Range
short int	-32768 to 32767
long int	-2147483648 to 214743648
signed int	-32768 to 32767
unsigned int	0 to 65535

return

The return keyword terminates the function and returns the value.

int func() {
    int b = 5;
    return b;
}