2. HARD DISK DRIVE
A HDD is the most common storage device used in PC’s. it uses
magnetic disks and a needle to read/write on the disks. Disks are
otherwise known as platters. The maximum possible 3.5’’ HDD capacity
is 4TB and there is 1000GB on each platter. HDD’s have the larges
capacity and are the most common. Older HDD’s use a IDE/PATA
connection where new HDD’s use SATA connections.

3. Optical Storage
Optical storage is a layered disk that is read by a laser. There are different types of disk and
these are the most common: DVD, Compact Disk and Blu Ray. Compact disk is a optical disk
that has been developed to hold audio. A Digital Versatile Disk (DVD) is designed to hold
data. A Blu Ray disk is designed to hold HD video and have a high capacity.
Type Capacity Write Speed Read Speed
CD 700MB 1200 Kb/s 1200 Kb/s
Single Sided 4.7GB
Single Layer
Single Sided 8.7GB
Double Layer
10.5 Mbit/s
DVD 10.5 Mbit/s
Double Sided 9.4GB
Single Layer
Double Sided 17.08GB
Single Layer
Single Layer 25GB
Blu Ray Double Layer 50GB 4.5MB/s 4.5MB/s
80XL 100/128GB

4. Flash Memory
Flash memory is a non-volatile storage chip that’s is electronically written and
read. It is used by memory cards, solid state drives and USB thumb drives. Flash
memory has the fastest read and write speeds as it is using a mainboard to
house the chip. The speed however will be limited by what it is carried by like
USB. Flash memory chips has a maximum capacity of 8GB.

5. Magnetic Tape
Magnetic tape is a storage media that has been around since the 1950’s. It was
the first used to record data in 1951. Magnetic tapes are made up of two reels
and the tape is written on as it passes through a magnetic head. Then to be read
the tape must be re wound to the place it was written to, to be read. The highest
capacity tape cartridges can store up to 5TB of uncompressed data.

6. PATA
Parallel ATA is a connection/cable that connects a HDD or a Optical Drive to a
Motherboard. It has been around since 1986 and PATA has been replaced by
SATA in 2003 due to its high speeds and smaller connection. PATA uses 40
individual cables that allows the motherboard to communicate with the
HDD/optical drive. PATA data transfer rates are between 16 MB/s and 133 MB/s
carrying only 16 bits of data.

7. SATA
Serial ATA is a cable for connecting HDD/Optical Drives to motherboards. It
replaced PATA in 2003. SATA has a 7 pin data connector and a 15 power
connector. There are three revisions of SATA, SATA I which has data transfer
rates of 1.5 Gbit/s, SATA II which has data rates of 3.0 Gbit/s and SATA III which
has data transfer rates of 6.0 Gbit/s.