The vocabulary derives primarily from Romance languages, with some of it influenced from Germanic languages.

Esperanto's vocabulary, syntax and semantics derive predominantly from languages of the Indo-European group. Within the range of constructed languages, Esperanto occupies a middle ground between 'naturalistic' (imitating existing natural languages) and a priori (where features are not based on existing languages). The word esperanto translates into English as 'one who hopes'. Early adopters of the language liked the name Esperanto and soon used it to describe his language. Esperanto's International Language (Esperanto: Unua Libro), which he published under the pseudonym Doktoro Esperanto. Zamenhof first described the language in Dr. Zamenhof in 1887, it was intended to be a universal second language for international communication, or 'the international language' ( la Lingvo Internacia).

Created by the Warsaw-based ophthalmologist L. Esperanto ( / ˌ ɛ s p ə ˈ r ɑː n t oʊ/ or / ˌ ɛ s p ə ˈ r æ n t oʊ/) is the world's most widely spoken constructed international auxiliary language.

Essential grammar in use second edition