Licensing

A license is the set of restrictions on what you can do with a game.

Source code and binaries (compiled executables) may have different licenses. A source code license restricts the use and availability of code, the binary license restrictes the use and availability of the game. To play a game, you usually only need to be concerned with the binary license. However, if the game is not available on your platform, or you have political objections to closed sourced proprietary software, the code license can also become important.

Usually, if the source code is available, the game is freeware. However, some games may license the art assets separately from the code. Thus, the code may have no cost, but the art assets may require a purchase. The "game license" is taken to be the most restrictive of these licenses.

This is not a legal definition. Many other sites go into exhaustive depths as to the nuances of these different licenses.

Source licensing:

• Closed source: The source code is not available to the public. Only pre-compiled binaries are available.
• Source Code Available: The source code is available but you are not allowed to reuse it, even if you release your derived works.
• GPL: The source code is available, but if you use it in your code, you must release it as GPL.
• BSD: The source code is available and you are allowed to reuse it in your code, even if your code is closed source.
• Open Source: The source code is available. This term is used for several different licenses, so it is usually helpful if a more exact term can be used.

Game licensing:

• Commercial: You must purchase the game before you can play it, and must not share the game with others. Many commercial games provide demos, which conflates Commercial with Shareware. Often the (arguably poor) distinction is made that Commercial has a box in a store shelf, while Shareware is internet only.
• Crippleware: You can download and play the game without paying the original author; however, the game is limited in some way. For example, you can only play it for a certain length of time, or only part of the game is available, or some features are missing. To play the full game, you must purchase it. You are usually free to share the shareware version of the game with friends, but CD compilations are sometimes frowned upon. It is suggested that you contact the author before you redistribute in a large scale. Crippleware is often called shareware, because that sounds nicer.
• Shareware: You can download and play the game without paying the original author; however, you are morally obligated to pay the author if you like it enough to keep playing. Sharing and redistributing the game are encouraged.
• Freeware: You can download and play the game without paying the original author. There is no limited time period to play the game and the entire game is available to you. While you can freely give the game to your friends, many freeware authors frown on CD compilations. It is suggested you contact the author if you wish to redistribute in a large scale.
• Postcardware: Freeware license terms apply. If you would like to thank author for creating and maintaining a game you are encouraged to send him/her a postcard.