The user interface is very intuitive and easy to use. It finds duplicated files of up to 4 GBs.
The search algorithm is specially effective and it will have searched your HD in a few minutes. Then, you'll have a list of duplicated files and you'll be able to do whatever you want with those files.
Choose the ones you want to keep and eliminate the rest.
Why are you wasting your HD? Eliminate duplicate files, your system will be grateful to you.