Answer 1

There are variable types for many different types of numbers, and these vary by programming language. I’m most familiar with Java.
Variable Types

char
a single character
must be in ‘single quotes’
Size: 2 bytes
ex. ‘C’  ‘z’ ‘!’  ‘%’  ‘ ‘

String
a string of characters
must be in “quotes”
Size of Strings depend on how long they are

byte
number
Size: 1 byte

short
number
Size: 2 bytes

int
an integer (whole) number
Size: 4 bytes
Ex. … -3, -2, -1, 0, 1, 2, 3…

long
A long number
Size: 8 bytes

float
a floating point decimal number
Size: 4 bytes

double
a floating point decimal number
Size: 8 bytes

boolean
true or false
Size: 1 byte