The term drive checker is self-explanatory. Hard drive is prone to failures, errors with respect to file system, registry errors etc. makes it more prone to failures. Remo MORE drive checker has two methods to check the drive for better/fast performance and those are Normal Analysis and Thorough Analysis.
Normal analysis would check for the file system errors on the selected drive and fix it.
Thorough analysis would check for the bad sectors on the drive and recovers the readable information on the drive.