For OOP programmers or general ones, what plan or methodology do you use for deriving variables ? Suppose this in design phase of the programme ( Before I do sniper, its "kungu-fu" skunk a simple 2D game similar to super mario to see if I can do this thing.... ) : Assume that I'm writing a game plan for a game called "kungfu-skunk" . I have created a requirements and design plan. Some of my basic requirements are these : - Player can move left / right of screen - Player can jump - Player can box and kick opponents I've already defined my Player Object, classes,methods and properties. What would be variables for Player and how can I derive these? I know one is position on screen. Rgds -- "..the game you imagined and the game that will result may not have a lot in common. Rapid prototyping is key.. " - someone.