Question

What is difference between register_name and register functions in Erlang?
Both register a PID as a name!

Answer 1

Digging up the documentation, I discovered that register() is part of the erlang module while register_name() is part of the global module. So, it appears the main difference between the two functions is that register_name() will register a name globally for a network of Erlang nodes.

The ability to globally register names is a central concept in the
programming of distributed Erlang systems. In this module, the
equivalent of the register/2 and whereis/1 BIFs (for local name
registration) are implemented, but for a network of Erlang nodes. A
registered name is an alias for a process identifier (pid). The global
name server monitors globally registered pids. If a process
terminates, the name will also be globally unregistered.

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