Semantically:

• A throw is meant to be caught by you (typically within the same module that throws), can be any term

• An error is when something goes wrong (typically not rescued), it is an exception in Elixir

• An exit is when a process is crashing (typically not caught), can be any term

throws are handled by catchs, errors are handled by rescues. If I had a magic wand, exit would not be part of the language, especially because it is often mixed with the separate exit signal, but it exists in Erlang, so we have to support it, hence the catch kind, reason -> notation.

PRs to improve the docs are always welcome.

I would treat try/catch as a control flow (goto-like,) while try/rescue as handling an exceptional situation.

rescue is a shorthand, mostly. catch can do its job, but there’s more boilerplate and some of the shapes aren’t as nice:

try do
  1 + :foo
rescue
  e ->
    IO.puts "OH NO #{inspect(e)}"
end

(prints OH NO %ArithmeticError{message: "bad argument in arithmetic expression"})
versus

try do
  1 + :foo
catch
  :error, e ->
    IO.puts "OH NO #{inspect(e)}"
end

which prints OH NO :badarith

Using catch in this way also means that Erlang errors are not transformed into Elixir exceptions - note the different inspect output for the two cases.