# stddef.dm file

Source: https://ref.dm-lang.org/appendix/stddefdotdm

This is a special file that's included in all projects when you compile. It contains various constants, definitions of some built-in datums, and so on.

You can see the contents of this file by creating a new file in Dream Maker called `stddef.dm`. It will automatically be filled with the standard definitions.

The contents of `stddef.dm` may change with new BYOND versions. However an eye is always kept on backwards-compatibility.