ABSTRACT
Sometimes game programmers start from scratch. They pick up a programming language and just start writing code to create a game world, add gravity to objects, check for collisions between objects, and so on. Other times developers will use code libraries that have been written by others to provide much of the functionality developers need to quickly create a game. Very often, game developers use game engines that not only offer a large library of code for common functionality needed in games but also provide a visual interface for building the games.
