I'm sorry if this is in the wrong section, but I didn't know where else to put it. I am making a game with Java, and I want the user to be able to save they're progress on their computer. In order to do this, I want to create a new type of file to save it as such as .doc or .ppt. I apologize if this is a stupid question, but how do I make a new file type to save the game data? I am using Mac OSX 10.7.