Yes, today (December 15th) is Zamenhof day, the birthday of Ludwig Zamenhof. He is the man who created Esperanto.
This "holiday" stretches back to 1878, when Zamenhof first told birthday well-wishers about his new language. Today, most esperantists celebrate by purchasing a book in Esperanto.
While Esperanto is hardly the universally spoken second language that it was intended to be, it is far and away the most successful constructed language with several million speakers. And, more importantly, in an increasingly international world, where people from various cultures mix on a daily basis, the idea of a neutral auxiliary language has never seemed more apt.
Zamenhof grew up in a city divided by multiple languages, where the people mistrusted one another due to incomprehension. His idea was to create this neutral second language for them so that they could begin to communicate. He thought that most conflict arose from misunderstanding and from the fear produced by not communicating.
The discussion of English as a global language must wait for another post. Today we simply acknowledge Zamenhof and his ideals.
Estu bone kaj havu bonan Zamenhofan tagon.