Whats with var ?

Question

why am I supposed to write var while I can use anything else and its also faster . is there anything about this data thing? I don't get the data part.

Answer 1

var·i·a·ble
/ˈverēəb(ə)l/
noun ~` an element, feature, or factor that is liable to vary or change. In programming, variables are used to store values which can be used for later purposes (e.g. calculation, modification).

(var keyword tho, https://stackoverflow.com/questions/4307467/what-does-var-mean-in-c)

Answer 2

we are supposed to write var because it represents a variable