Earlier drives had a tendency toward developing bad sectors with use and wear; these bad sectors could be "mapped out" so they were not used and did not affect operation of a drive, and this was considered normal unless many bad sectors developed in a short period of time. Some early drives even had a table attached to a drive's case on which bad sectors were to be listed as they appeared. Later drives map out bad sectors automatically, in a way invisible to the user; a drive with remapped sectors may continue to be used. Statistics and logs available through S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) provide information about the remapping.