CCleaner is a utility by the Piriform company for cleaning out a computer. It is capable of removing temporary files, broken shortcuts, browsing history and a number of other potentially unwanted files, as well as uninstalling programs and modifying programs that run at startup.
Sometimes called CrapCleaner, according to the Piriform website, CCleaner is a small utility that can be used to increase privacy, security, speed, stability and space. It accomplishes this by deleting Internet files, wiping free space clean, cleaning the registry and removing duplicates throughout the computer system. The professional version can also clean online traces in real time.