Two, it erases private data like your browsing history and list of most recently opened files in various programs. One, it scans for and deletes useless files, freeing up space. The real question we should be asking is: do you really need CCleaner in the first place? CCleaner Is Disk Cleanup On SteroidsĬCleaner has two main uses. It’s widely recommended, online and offline-but this week, it acted as a piggyback for malware. These days, it seems like every Windows user has heard about CCleaner.