[dnanian]

MySQL is the database that comes with OSX. If you're not using it, you probably don't have to dump the databases, but I regret that a MySQL tutorial isn't something I can offer here (though if another user here on the forums has the time to explain how mysqldump works, I'd appreciate the chip-in).

Basically, you'd use the mysqldump command to dump the databases, which generates a nicely checkpointed version that can be restored later, should it be necessary. Without that step, you might be backing up a "live" database file, which isn't guaranteed to be in "closed" state at the time of backup.