1. A method performed by a computer system having a processor and memory to improve document translations, comprising: receiving a request for a translated document in a preferred natural language; retrieving an identified document, the identified document storing text in a first natural language; translating using the processor the retrieved document to create the translated document containing text translated into the preferred natural language wherein the preferred natural language is a natural language that is not the first natural language; providing the translated document; receiving a modification to a word in the translated document; storing the received modification to the translated word to improve a subsequent request for the translated document; receiving a subsequent modification to the translated word in the translated document; and storing in the storage the received subsequent modification to the translated word; upon receiving the subsequent request for the translated document, retrieving the identified document; translating the retrieved document into the preferred natural language; selecting either the modification or the subsequent modification based at least on an identification of users who made the modifications and a relative trustworthiness of the users, wherein the trustworthiness of a user is based on how many times other users modify a modification made b the user; retrieving the selected modification; modifying the translated document based on the retrieved modification; and providing the modified translated document.
9. The method of claim 1 further comprising providing a stored modification to a machine translation learning system to improve future machine translations.