The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces.

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.

In the late 1970s, General Instruments produced an electrically alterable ROM (EAROM) which operated somewhat like the later NAND flash memory.

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HDDs are a type of non-volatile storage, retaining stored data even when powered off.

HDDs became the dominant secondary storage device for general-purpose computers by the early 1960s.

For applications requiring fast access but not necessarily data persistence after power loss, SSDs may be constructed from random-access memory (RAM).

Such devices may employ batteries as integrated power sources to retain data for a certain amount of time after external power is lost.

Hybrid drives or solid-state hybrid drives (SSHDs) combine the features of SSDs and HDDs in the same unit, containing a large hard disk drive and an SSD cache to improve performance of frequently accessed data.

but they were seldom used because of their prohibitively high price.

A is the entire path from the root of the volume it resides on to the end of the file name.

For example, here is the file specification for the Terminal application: /Applications/Utilities/Terminal This is known as a in geek terminology, but it's called a canonical filename for short.

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