Validating identity in wireless network
Later "Winchester" drives abandoned the removable media concept and returned to non-removable platters.
Like the first removable pack drive, the first "Winchester" drives used platters 14 inches (360 mm) in diameter.
The first IBM drive, the 350 RAMAC in 1956, was approximately the size of two medium-sized refrigerators and stored five million six-bit characters (3.75 megabytes), the 1301 used an array of heads, one per platter, moving as a single unit.
Cylinder-mode read/write operations were supported, and the heads flew about 250 micro-inches (about 6 µm) above the platter surface.
HDDs became the dominant secondary storage device for general-purpose computers by the early 1960s.
External HDDs remained popular for much longer on the Apple Macintosh.
IBM 2305 in 1970) so that no time was lost physically moving the heads to a track.
In 1973, IBM introduced a new type of HDD code-named "Winchester".
Data is accessed in a random-access manner, meaning that individual blocks of data can be stored or retrieved in any order and not only sequentially.
HDDs are a type of non-volatile storage, retaining stored data even when powered off.