Simplify the following text for a Grade 14 native English-speaking person.
Original: The text of Wikipedia is copyrighted ( automatically , under the Berne Convention ) by Wikipedia editors and contributors and is formally licensed to the public under one or several liberal licenses .
Simplified: The text contained in Wikipedia is copyrighted ( automatically , under the Berne Convention ) by Wikipedia contributors and licensed to the public under the GNU Free Documentation License ( GFDL ) .