Erlang is Ericsson's concurrent programming language.See Erlang Wikipedia for more information. Mochiweb is a web framework to create lightweight http servers written in Erlang language.
After creating a skeleton project with mochiweb (./scripts/new_mochiweb.erl). You can write your own code and compile it. Here is an article shows this in detail.
After all, running your new http server is done by star.sh or start-dev.sh in your application directory where you created by new_mochiweb.erl script. The script runs erl (The Erlang Emulator) command with some parameters. But it runs in foreground, if you want to run the erlang application in background simply add "-detached" parameter to your erl command. But, there is a drawback here. The erlang application runs in background and we cannot see the error and any information log messages now. I'll will explain how to log theses messages in log file and read them in another post.