GF (Grammatical Framework) makes it possible to perform multilingual authoring of documents in restricted languages. The idea is to use an object in type theory to describe the common abstract syntax of a document and then map this object to a concrete syntax in the different languages using linearization functions, one for each language. Incomplete documents are represented using metavariables in type theory. The system belongs to the tradition of logical frameworks in computer science. The paper gives a description of how a user can use the editor to build a document in several languages and also shows some examples how ambiguity is resolved using type checking. There is a brief description of how GF grammars are written for new domains and how linearization functions are de.ned.