how do you automate database backups?

Are there tools available to automate backing up databases? I would like
to setup my PostgreSQL install to automatically backup databases and
save the file to specific location at specific times of the day with
little to no user intervention... I'd like to know how to do this in
both Windows and Linux. I imagine I could write some kind of script or
something on my Linux server but I have absolutely no idea how to
implement this on a computer running Windows.

I would imagine this could be implemented through the OS but are there
built-in features of the database itself that can implement automated
backups?

Ferindo