Scratch is developed by the Lifelong Kindergarten Group at the MIT Media Lab, with financial support from the National Science Foundation, Microsoft, Intel Foundation, MacArthur Foundation, Google, Iomega and MIT Media Lab research consortia.
Scratch is a programming language that makes it easy to create your own interactive stories, animations, games, music, and art -- and share your creations on the web.
For those interested in programming and game development, this channel has videos on creating a game from scratch using Java. There are many similarities with GML; even if you are not interested in programming with Java, you can learn a lot of things useful in GM too.