Gleam is a statically-typed functional language that compiles to Erlang and runs on the BEAM VM. It combines type safety (catch bugs at compile time) with Erlang's legendary concurrency and fault tolerance. Gleam code reads like functional Python but runs with Erlang's robustness (99.9999999% uptime claims). For web backends, Gleam leverages BEAM's lightweight processes and supervisor trees for handling thousands of concurrent connections with graceful error recovery. Web frameworks (Mist, others) provide HTTP handling and routing. Message passing and process supervision replace traditional error handling.