"Yannick Duch�ne (Hibou57)" <yannick_duchene@yahoo.fr> wrote in message news:op.vdxjxcnqule2fv@garhos...

>What is a "drum memory" ?

It's behaves like a conventional disc in a disc drive.
Only instead of a set of platters bolted together and rotating
on the spindle formed from the bolt,
it's a cylinder rotating around its axis.

In the case of the disc drive, the surfaces of the platters are
coated with film capable of being magnetised.

In the case of the drum, the outside surface is coated with the magnetic film.