How do I wipe a Mac's hard drive completely?

Go away ShareBlue

A mac is just a pc ... so wipe dat shit like you would wipe any other pc hard drive.

DBAN
Parted Magic

Hold +R while booting.
Open Disk Utility from Recovery mode
There should be an option to write over the disk, set that to most secure.

Command+R to get to recover mode. For whatever reason, this site won't let me post the symbol for the command key.

>most secure
see you in 3 years.
Second one from left (0s + Random) is plenty, second from right to calm your autism down.