CCleaner is a freeware PC optimization tool.
It combines a system cleaner that removes unused and temporary files from your system and also a fully featured registry cleaner!
CCleaner allows Windows to run faster, more efficiently and gives you more hard disk space.
The best part is that it`s Small, Fast and Free!
Cleans the following Windows components:

* Internet Explorer
- Temporary File Cache
- URL History
- Cookies
- Hidden Index.dat files
- Last download file location
* Firefox
- Temporary File Cache
- URL History
- Cookies
- Download manager
* Recycle Bin
* Clipboard
* Windows Temporary files
* Windows Log files
* Recent Documents (on the Start Menu)
* Run history (on the Start Menu)
* Windows XP Search Assistant history
* Windows XP old Prefetch data
* Windows memory dumps after crashes
* Chkdsk file fragments

Advanced Options allow cleaning of:

* Menu Order cache
* Tray Notifications Cache
* Window Size and Location Cache
* User Assist history
* IIS Log Files
* Custom Folders

Application Cleaning:
As well as cleaning up old files and settings left by standard Windows components, CCleaner also cleans temporary files and recent file lists for many applications. Including:

* Firefox, Opera, Safari, Media Player, eMule, Kazaa, Google Toolbar, Netscape, Microsoft Office, Nero, Adobe Acrobat Reader, WinRAR, WinAce, WinZip and more...

Registry Cleaning:
CCleaner uses an advanced Registry Cleaner to check for problems and inconsistencies. It can check the following:

* File Extensions
* ActiveX Controls
* ClassIDs
* ProgIDs
* Uninstallers
* Shared DLLs
* Fonts
* Help File references
* Application Paths
* Icons
* Invalid Shortcuts and more...

Safety:
CCleaner was designed from the ground to be safe and secure to use. It has multiple levels of checks in place