Hard Drives (HD, HDD)
In the early days of personal computing, files and programs
were quite small by today's standards. They required little
storage space. Programs and files easily fit on floppy disks.
Even the OS (operating system) could be kept on a floppy to
be inserted and loaded into memory at start-up.
As the need for storage increased, tape drives
were used. These were very slow and storage was linear.
This meant that you had to 'fast forward' and 'rewind' the tape
continuously. Technology progressed fairly rapidly and program
and file sizes increased dramatically. Hard drives were introduced
in the early 80's, and the 5MB of storage space they
provided seemed to be more than anyone would ever use. Of course,
programs continued to become larger, more complex and diverse.
People now use computers for a wide variety of applications.
Today's entry-level computer has a hard drive with more than
13-20 GB of storage.
You'll often hear that the CPU and the motherboard
are the brain and the backbone of your computer, absolutely
necessary for the proper function and performance of you system.
However, a hard drive failure will definitely bring your computer
to a screeching halt. You can lose all your programs, information,
data, and your operating system. All you'll see is a flashing
cursor on your monitor and an error message indicating a hard
drive failure. Also, because your hard drive is a mechanical
device, it is more prone to failure.
At one time, the BIOS knew how the drive was
sectored (by calculating the information in setup) and would
access data through a controller card in an expansion slot on
the motherboard. Two cables ran from the controller to the drive,
one for information on where to position the read/write heads
and another to transmit data.
Today's hard drives have the controller and
a hard drive BIOS built right on the drive. Not only does this
setup control the read/write operations, but it performs many
other functions as well. One of which is to translate or interpret
positioning of data to the system BIOS. The system BIOS no longer
understands the physical organization of the platters inside