Mac Security Tip: Securely Empty Trash
When you place files in the Trash on your Mac, then empty the Trash, you may think that those files have been wiped from your hard disk; this is not exactly true. Emptying the Trash simply removes the catalog information (data on your hard disk telling your Mac where on the disk files are located), [...]
http://blog.intego.com/2011/04/13/mac-security-tip-secure-empty-trash/
