For most devices, some you can get rid of (those you down load) and some you can't (many of the preloaded). To remove the shortcut for an app on the home screen touch and hold the app until a trashcan appears then drag the app to the trash can. To uninstall an app go to Settings>Applications>Manage applications then touch the app you want to uninstall and choose uninstall. If you don't know what an app is or does, don't uninstall it and be careful with things like Market.