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Game Maker Programming/LibraryBuilder/Basics
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
To use the library builder you have to have a very good understanding of GML - the programming language of Game Maker. Not many people know it - but the libraries are simply made up of Game Maker code. All you are doing when dragging and dropping is putting small chunks of GML into the program, but it is represented by icons. To make your own library, you provide images, coding for the tab and sometimes initiation code.