LUA - GMS MAT_ What does it mean?

GMS, MAT_ what does it mean…heres a sample of the code ive been confused about

[lua]GMS.MaterialResources[MAT_CONCRETE] = “Concrete”
GMS.MaterialResources[MAT_METAL] = “Iron”
GMS.MaterialResources[MAT_DIRT] = “Wood”
GMS.MaterialResources[MAT_VENT] = “Copper”
GMS.MaterialResources[MAT_GRATE] = “Copper”[/lua]

Can anyone give me an explanation as to why it is like that etc and how it works?

I think it’s telling the gamemode what the material is either in a table or variable.

It translates MAT_ enumerations into strings for things such as menus and stuff.