Eraser is advanced security software that allows you to easily and completely remove sensitive data from your hard drive. It uses several redundancy techniques (such as multiple overwrites at the data plates, monitoring cache areas and data encoding techniques) which ensure 100% erasure that will stop even most sophisticated methods of data recovery.
If you thought that simply erasing data from your windows remove them completely, you are wrong. The only thing that is erased is its data reference from file system table, but erased files are still present on the data platters of your drive, where they will remain untouched until some other data overwrite it (and even then, it is possible to extract original data by studying magnetic fields on the disk platter surface).
All the techniques that were made to overcome these problems are present in Eraser, packed into easy to use interface that can be used by even inexperienced users.