[jQuery] how to make a easy show/hide menu by JQUERY

[jQuery] how to make a easy show/hide menu by JQUERY


JUST LIKE MORE TOP OR LEFT MENU,
like the top menu like this:
http://golf-clubs.best-buys.cn
or left menu like this:
http://www.alibaba.com/
is it easy to do,
can it easy to just write one line or two line codes do?
thanks