It looks as though it is used for complete data destruction. That means that if you use it on a hard drive, there will be literally no data left on it. Not only will it remove all files and the operating system, it will remove partitions. You'll be left with a completely blank hard drive. Not advisable for a rental laptop. I'd recommend something called a file shredder instead. A file shredder will revert all data for a specific file (or folder) to the default, binary "off state", where they are literally pristine, untouched space on your drive, and will appear to have never existed. (And can't be recovered, period. So, take warning) Also, take notice that even doing this to a small flash drive can take a while, so you might want to give it at least 24 hours to wipe all your data from the hard drive. (But be sure not to wipe anything that comes default with the rental laptop, though)
Glitchfinder, you're a man of such quirks(in a good way :P) about computers. Since I'm using a rental laptop and eventually I'll have to return it. Will using something like dban wipe all data, like the OS or just any written data?