Programming Elixir

System Types

These types reflect resources in the underlying Erlang VM.

PIDs and Ports

A PID is a reference to a local or remote process, and a port is a reference to a resource (typically external to the application) that you’ll be reading or writing.

The PID of the current process is available by calling self. A new PID is created when you spawn a new process. We’ll talk about this in Part II.

References

The function make_ref creates a globally unique reference; no other reference will be equal to it. We don’t use references in this book.