Ido (/ˈiːdoʊ/) is a constructed language derived from a reformed version of Esperanto, and designed similarly with the goal of being a international auxiliary language (or universal second language) for people of diverse languages. To function as an effective international auxiliary language, Ido was designed specifically to be grammatically, orthographically, and lexicographically regular (and, above all, easy to learn and use). It is the most successful of the many Esperanto derivatives, known as Esperantidoj.
Ido was created in 1907 due to a desire to reform the perceived flaws of Esperanto, a language that had been created 20 years earlier to facilitate international communication. The name comes from the Esperanto word ido, meaning "offspring", since the language is a derivative of Esperanto. After its inception, Ido was endorsed by some of the Esperanto community. A setback occurred with the sudden death in 1914 of one of its most influential proponents, Louis Couturat. In 1928, promoter Otto Jespersen quit the movement for his own language Novial.
