8/22/2007 -- Regular format wipes out the files on the drive and scans the hard drive for bad sectors. That's why using the regular format takes longer; quick format doesn't check for bad sectors and is therefore quicker. Other than that, there's no visual difference or effect that's readily noticeable.

The recommendation is to run regular format when you're formatting your drive for the first time. This will ensure that the bad sectors are detected and your data will be less likely to become corrupted.

Quick format is the preferred method on drives that have been previously formatted. Even if you've performed a quick format on a partition, you can always run CHKDSK /R afterward at the command prompt to fix any possible errors.