Zamenhof Day or International Esperanto Day
Zamenhof Day or International Esperanto Day is held on December 15. International Esperanto Community. This event in the second decade of the month December is annual. 
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Esperanto is a popular constructed international auxiliary language. There are over 2 million Esperanto speakers worldwide. Esperanto is a constructed language created by a Jewish-Polish ophthalmologist in the late 19th century.
Esperanto was constructed to be easy to learn, and it will sound familiar to speakers of European languages. It was created in the late 19th century by Ludwik Lejzer Zamenhof. After years of work on his new language, Zamenhof published Unua Libro in Warsaw on July 26, 1887. He published it under the pseudonym Doktoro Esperanto, which means “Doctor Hopeful,” and the latter half was adopted as the name of the language.
The language was initially known as “International Language” but the early speakers began referring to it as Esperanto in 1889.
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