My wife has an old iMac with a defective screen that has vertical lines running down it. Even if parts were available for it (they aren't) it is not worth repairing. However, before I throw it away, I ought to erase the hard drive. It is doubtful that there is any damaging or controversial data on it (it hasn't been turned on in years) so it doesn't need any kind of ultra-secure wipe.

If it were a Windows computer it would be easy, but I know less than nothing about Macintosh. (Less than nothing means that what little I do know is probably wrong.)

What should I do?

tanstaafl.