Esperanto is the most widely spoken constructed international auxiliary language. The name derives from Doktoro Esperanto, the pseudonym under which L. L. Zamenhof first published the Unua Libro in 1887. The word itself means 'one who hopes'. Zamenhof's goal was to create an easy and flexible language as a universal second language to foster peace and international understanding.

Although no country has adopted the language officially, it has enjoyed continuous usage by a community estimated at between 100,000 and 2 million speakers. By some estimates, there are about a thousand native speakers.

Today, Esperanto is employed in world travel, correspondence, cultural exchange, conventions, literature, language instruction, television (Internacia Televido) and radio broadcasting. Some state education systems offer elective courses in Esperanto; there is evidence that learning Esperanto is a useful preparation for later language learning.

Links:

http://en.wikipedia.org/wiki/Esperanto
http://eo.wikipedia.org/wiki/Esperanto
http://esperanto.net
http://esperanto.org
http://lernu.net

Slovensky:

http://esperanto.sk
http://sk.wikipedia.org/wiki/Esperanto
http://sk.lernu.net