MS DOS DEL versus ERASE

Long ago in the MS DOS days. I recall being told that there was a difference between the DEL and ERASE commands. One just deleted the directory entry for the file (and therefore the file could in theory be restored), the other actually erased all the data from all the sectors that file was stored on (better for security).  However, although it would seem that intuitively DEL would do the former and ERASE  the latter, I also recall being told that the commands were not intuitively named, though that source wasn’t reliable.

Doing a Google search has turned up a plethora of sites on these commands, but all the ones I checked claim that both commands do exactly the same thing. Can anyone help me out here with the correct information on these two commands? Thanks!