Integer
From Legacy Roblox Wiki
< Scripting | Data Types
An integer is classified as any number that has no fractional component.
Example
These are all Integers:
5, 45213, 753, -4256, -842,
These are NOT Integers:
5.3, 636.24
Explanation
Integers are used when you need a number with no decimal place or it doesn't make sense to have a decimal. Because integers are whole numbers, there are no integers between 1 and 2.
In IntValues, the lowest value it can hold is -231 or -2,147,483,648. The highest value it can hold is 231-1, or 2,147,483,647. For the computer geeks out there, this is a 32-bit (or long) signed integer value.
In Lua scripts, there are no specific integer numbers. The number values are actually double precision floating point (or just 'double') numbers.