# How to Contribute#

There are three repositories:

lit: the literature library

ex: the expansions and examples library

en: the English translations library

To contribute to any of these, visit its site at GitHub, and follow instructions there. Contributions may take many forms:

**Represent an existing proof:**If you are studying historical mathematical literature, you can help build lit by translating a proof into the Proofscape language.

**Write an expansion:**If you should study a proof in lit and become stuck on a difficult step, only to eventually figure out how to fill in a few additional steps and make the inference clear, you can record your work in the form of an

*expansion*in ex. Your expansion will then be available for anyone else who may become stuck on the same step.**Make a comparison:**It sometimes happens when reading a proof, that one step stands out as reminiscent of a similar step from another proof. This is a valuable observation, helping to form a foundation for a history of proof ideas, and may be recorded by adding a

*cf reference*in lit.**Write an example explorer:**Many proof steps could be more easily understood if only it were possible to rapidly produce an assortment of numerical examples of the types of objects involved at that step. You can facilitate this by building an

*example explorer*in ex.**Write an English translation:**Much of historical mathematics was published in languages like French, German, Latin, or Russian. You can help make these materials more accessible by contributing an English translation in en.