Article development led by
While the ubiquitous SSD shares many
features with the hard-disk drive, under
the surface they are completely different.
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oVer the past several years, a new type of storage
device has entered laptops and data centers,
fundamentally changing expectations regarding
the power, size, and performance dynamics of storage.
The solid-state drive (SSD) is a technology that has
been around for more than 30 years but remained
too expensive for broad adoption.
That changed with the introduction
of consumer products such as the Apple iPad and iPhone, which led to the
widespread availability of cheap nonvolatile memory. Manufacturers have
attempted to use this consumer-grade
material to produce SSDs and make
them look and act as much as possible
like hard-disk drives (HDDs). Under
the surface, however, they are completely different.
An HDD uses a head mounted on a
mechanical actuator to access rotating
magnetic storage media. In contrast,
an SSD uses nonvolatile memory (that
is, NAND flash) as its storage media.
The lack of moving parts and the use
of silicon as the media give the device
the “solid-state” name. This attribute
makes SSDs less fragile than HDDs. As
such, SSDs are common today in mo-
bile devices such as smartphones and