If you’ve just bought a new computer, selling off your old can be a good way to recoup some of the cost, but before you hand over your old system to a buyer, you need to wipe all your personal information from it.
Simply reinstalling the operating system isn’t enough as technically speaking your old data is only hidden and could still be recovered so you need securely erase that information.
For windows systems you can use a free program like CC Cleaner, or DBAN. For Mac head to the Disk Utility application where you’ll find everything you need to wipe your hard drive clean of all traces of you.
