There are some interface things to be aware of as well. When providing in-game instructions and controls, it's important to know the difference between a Windows and Mac keyboard. i.e. on Mac, there is no "enter" key, it is called "return" on Mac. When programming controls you can still use <enter> events or vk_enter in code to check the return key, but you should probably refer to it as return and not enter when telling the player the controls visually.