[CODE] command

I find it pain to add a double space at the beginning of each line if
I want to add a big chunk of code to my pages.

Is there any other way of putting in code?
Some bulletin boards have a [CODE] [/CODE] command that contains the code.

I know that those commands are specific to those boards, but I was
wondering whether the principle could be applied.
i.e. only need a command a the start and at the end of the code block
instead of on every line

/Andrew