Numbers are mathematical values that play a huge role in programming. In Scratch, they are used for optimizing and making algorithms function properly. Without numbers, addition, multiplication, etc. would not be possible. Numbers are also used as identifiers in Scratch, such as the costume # value, which identifies the placement of a costume in a sprite.

## Number Line

A number line can be used to represent integers and the values in between them. The following image depicts a number line:

## Blocks

Many blocks take a number parameter, or a small bubble that allows one to enter a number. The operators blocks in particular deal with numbers and many simple to advanced mathematical concepts. A variable can contain a number value and is often used as value-storing for varying purposes in a project.

## Project Identification

Every project has an ID number found in the URL specific to that project. It is used to single out which project is which in the Scratch server.