Here's why:
* Widespread use: Esperanto has a significant number of speakers worldwide, estimated to be in the hundreds of thousands.
* Long history: Created in 1887 by L.L. Zamenhof, it has been around for over a century and has a rich history and culture.
* Active community: There are numerous Esperanto clubs, organizations, and events happening around the world.
* Resources: There are many learning materials available, including books, websites, and online courses.
* Regular usage: Esperanto is used for communication, literature, music, and even in some academic contexts.
While other constructed languages exist, like Interlingua, Volapük, or Ido, none have achieved the same level of recognition and use as Esperanto.