Component's are a snipnets of code which are designed to provide extra functionality to various objects that contain a ComponentManager. Objects do not have to have Components in order to preform their main function, but are instead provided to make common task's that you may want to do with those Objects a bit easier. For example: Some times you would like to easily listen for when a GameObject has been 'clicked'. So you can attach a 'InputComponent' to a GameObject (Sprites have them by default) which will then do hit-detector code for you. All you have to do is Subscribe to the events on the InputComponent.