There are many different cleanup utilities, and they can be easily classified. To begin with we can define the set of the 'disk cleaner' or 'file cleaner' class utilities including CCleaner, a freeware program which helps you clean up unnecessary files and give back usable space in the process. Another class is the Privacy Cleaner style utilities which delete internet history and delete traces of things you have typed while searching stored as history within your browser records, tools such as Evidence Eliminator. Now there is also porn detection software which detects the existence of porn and inappropriate material and helps the user get rid of the ones that should not be there. And a final category of programs comprising disk 'washing' software which can overwrite with 1s and 0s, random data from anywhere on the disk so it cannot be misused.