GML Do All Rooms and their content load into memory?

[Jason C.]

On game start, do all Rooms and their content load into memory? Or do Rooms load and load all their content (off disk) when I call something like "room_goto()". Likewise, when the Room is closed and another loads, is the old Room and its contents removed from memory?

 

[TheouAegis]

loaded when first visited

removed from memory when left, unless flagged as persistent