Internal Storage Devices
Storage devices that are installed inside your computer are called internal
storage devices. Generally, you cannot remove such devices when the
computer is powered on. The data stored on internal storage devices
is generally stored till you manually delete it. Internal storage devices
include hard drives (HDD) and solid-state drives (SSD).
An HDD contains magnetically coated platters that rotate on a
motor-driven spindle, within a protective enclosure. Data is magnetically
read from and written to the platter by read/write heads that are
present above the platters. The hard disk drive is the data center of your
A typical HDD design consists of a spindle that holds flat circular disks
called platters, onto which the data is recorded. The platters are made
from a non-magnetic material, usually aluminum alloy or glass, and are
coated with a shallow layer of magnetic material, with an outer layer of
carbon for protection.
An SSD is a data storage device that uses solid-state (flash) memory to
store data. SSDs contain no moving parts as data is stored in electrical
circuits. Compared to HDDs, SSDs are typically less susceptible to
physical shock, are quieter, and have lower access time and latency.
SSDs use the same interface to connect to the computer as HDDs,
making them compatible with most existing computers.
Removable Storage Devices
Removable storage devices that you can remove from your computer
without turning the computer off are called removable storage devices.
Commonly used removable storage devices include:
• Optical discs
• Memory cards
• Magnetic tapes