Unruh wrote:


>> You can use heads that are much narrower than the normal read head.
>
> And yu think they do not use read heads which are as narrow as possible
> now? How do you think they get terrabytes on a tiny disk that once held
> 10MB for the same area?


Not because the heads got narrower; they're rather fucking huge, and only a
very fine control of positioning and signal strength makes it possible to
record high density. Indeed, if you just judge by the size of head, we'd
still dig around with 10 MB per plater.