Lernu! is a website hosting several free multilanguage courses designed to teach Esperanto. The site features courses catering to different levels of difficulty, featuring vocabulary words, drills, and grammar instruction. Students who encounter an unfamiliar word can click to immediately see a translation in their language. Tutors grade the course by hand, and also answer any questions about the language. The site was launched December 21, 2002.

The site also contains Esperanto books and music, electronic mail and instant messenger-like services for registered users, games, forums, and information about upcoming Esperanto conferences.

Languages covered by Lernu! as at 20060415:

en English

ca Catala

cs Čeština

da Dansk

de Deutsch

eo Esperanto

es Espanol

fi Suomi

fr Francais

he עברית

hr Hrvatski

hu Magyar

it Italiano

ko 한국어

lt Lietuvių

nl Nederlands

no Norsk

pl Polski

pt Portugues

ru Русский

sk Slovenčina

sv Svenska

zh-cn 簡体中文

zh-tw 正體中文