When you think of a computer, chances are good that you
imagine the case; the computer as a whole. However, what
would you identify as the most important part of the
computer? Would you point to the motherboard? Perhaps you
would say that the processor is the most important part of a
While these are certainly vital aspects to an operating
computer, the disk drive is just as important. Over the
years, they have gone through many changes and have evolved
considerably. The first hard disks were technically
"external" devices, because they sat outside the case,
contained within protective covers. However, to modern users
these would hardly be considered hard drives, as their
storage capacity barely reached 5MB.
The Earliest "External" Drives
The very earliest hard drives were external for all intents
and purposes. This is because they were not mounted within
the computer frame. These devices debuted in the late 1950s,
could store 5MB of data and shipped with the first
commercially available IBM systems. Over the next few
decades, things did not change very much, as computer use
was largely relegated to commercial interests and the home
PC had yet to be invented.
Almost 30 years after the debut of those systems, IBM
brought out the first gigabyte drive. This device was the
size of a household refrigerator, and was a separate unit
from the computer. It retailed for a whopping $40,000.
The Intervening Years
Between the debut of the personal computer and the release
of what a modern consumer might recognize as an external
hard drive, there were several innovations. However, most of
these were strictly for internal drives, as the need for an
external drive was not particularly great with early
One of the first systems to make use of an external hard
drive was Apple. Their computers often had drive bays that
were difficult to access, and some had no hard drive within
them at all. In an era where computer users started to
demand safer storage for their precious data, this could not
work. Therefore, Apple introduced the ProFile in 1983. It
worked by connecting to a special port on the back of the
Apple II. This hard drive offered 5MB of disk space, though
a 10MB was offered later as an upgrade.
It was during this time that internal drives began to take
on their standard form factors. In fact, the shape of the
hard drive stopped changing early on with the development
and standardization of IDE technology, with a size and shape
that has barely changed since those early years. The most
popular form factors have included 5.25", 3.5", 2.5" and 1"
consumer form factors.
Additionally, any of these drives could be setup as an
external drive, so long as power and data cables were able
to be connected to the drive outside the computer case. Of
course, these were not what most people would consider
"removable media" in the sense of modern external hard
drives, flash drives and other storage devices.
1998 and Beyond
The year was 1998, and a revolution was brewing in the
computer industry. This was the time when the USB interface
was introduced to computers. This ground-breaking technology
enabled any type of device to connect directly with a
computer from the outside, using the same type of interface.
Previously, hard drives made use of a 40-pin connector and a
power cable (internal types and most external types).
However, with the advent of USB technology, this was to
This single technology allowed different external hard drive
designs to proliferate. It also enabled the birth of other
removable media, such as the flash drive (thumb drive). Of
course, the first external USB drives were bulky things, due
to the technology available in 1998. As the year 2000 loomed,
technological advances in computing were moving at a rapid
As more efficient power sources and cooling solutions were
developed, the size of external drives shrank. Once clunky
and cumbersome, these drives became streamlined and small.
Today, you can find myriad different sizes on the market.
The most popular type (for consumers, at any rate) is a bit
larger than a thick paperback book. However, these solutions
are not intended to be portable. Manufacturers designed these
for backup and storage where the drive stays in one place,
and might hold several terabytes of data.
Portable external drives were soon to hit the market. These
offered storage capacity in the hundreds of gigabytes,
though they did not rival larger drives in terms of storage.
Portable drives became extremely popular, particularly with
those who used the drive at work and at home, as well as
with students who needed their data available to them on
numerous computers in different locations.
A further development that came about with the growth of the
interconnected home, is the advent of network attached hard
drives. These drives must be connected to the home network
router, but they do not have to be connected to a computer
in order to function. The router acts as a gateway, enabling
data transfer between the computers and other devices within
a home and the hard drive. This is an excellent solution for
homes where media is used heavily, and many drives have
specific built-in servers for different media types,
including iTunes, games and movies.
A Glimpse of the Future
In the future, the external hard drive is expected to assume
more and more a central role in home computer use. As
computing devices shrink and "tablets" and netbooks come to
the fore as preferred technology, external drives will need
to be available for immediate access to stored data and to
provide immediate backup, as well. Integreation in networks
will be a must for consumers, and as technology advances it
will provide some innovative solutions. Some examples
include integrated router/hard drive units, as well as
central server/hard drive solutions for media and
About the Author:
Ed Molino is a staff member of smalldrives.com specializing
in the support of their network hard drives. Fancy an
external hard drive? Find quality drives at