Airkit provides a built in set of Types. A Type is a classification of data based on what it can do with that data. When discussing a particular piece of data, we refer to it as a value. Every value in Airkit has an associated Type, or classification. It is important to consider the type of a value because the Type determines what can be done with it. For example, it makes sense to subtract two Numbers 3 - 2, however, it would not make sense to subtract two pieces of text "Hello" - "Airkit".