There seems to be a lot of Beam languages but I’m curious to know which ones are the most used.
Obviously there is Erlang
Erlang was designed with the aim of improving the development of telephony applications. The initial version of Erlang was implemented in Prolog and was influenced by the programming language PLEX used in earlier Ericsson exchanges.
Elixir is a functional, concurrent, general-purpose programming language that runs on the Erlang virtual machine. Elixir builds on top of Erlang and shares the same abstractions for building distributed, fault-tolerant applications. Elixir also provides a productive tooling and an extensible design.