Storage Devices
What is a storage device?
• Hardware that reads from and write to different storage media
• Non-volatire secondary storage, that retain digital data within a computer system
• Provide a means of storing, accessing, and retrieving data, which can include software
applications documents, images, video and more.
• 3 types of storage device:
o Magnetic
o Solid-state
o Optical
Magnetic storage:
• Non-volatile media and use magnets. (stores binary 0s and 1s)
Advantages of magnetic storage:
• Capacity – high storage
• Cost – low per gigabyte
• Speed – moderate
Disadvantages of magnetic storage:
• Durability – moving parts can get damaged if dropped
• Portability – heavy and bulky making them less convenient for transport
• Reliability – prone to mechanical failure
• Noise – loud (spinning disks)
Solid-state storage:
• Solid state storage is a type of non-volatile media that uses electronic circuits to store binary 0s
and 1s.
Advantages of solid-state storage:
• Capacity – medium/high storage
• Speed – very fast read/write access
• Durability – small and no moving parts
• Noise – silent
Disadvantages of solid-state storage:
• Costs – very high per gigabyte
• Reliability – limited read/write cycles
Optical storage:
• Non-volatile media that uses laser to burn the surface of a disk, creating pits and lands suitable
for storing binary 0s and 1s.
Advantages of optical storage:
• Cost – very low per gigabyte
• Durability – no moving parts
• Portability – small and no moving parts
• Noise – silent.
Disadvantages of optical storage:
• Capacity – very low
• Speed – very slow read/write access.
• Reliability – prone to scratches
HDD – Hard disk drive (storage media):
• General – purpose storage capacity
• Large storage capacity (5TB) relatively fast
• Moving parts, vulnerable to physical damage
• Magnetic storage device
Portable hard disk drive (storage media):
• External storage for data transfer and backup
• Portable (5TB) large storage capacity
• Slower than SSDs, vulnerable to physical damage
• Magnetic storage
Magnetic tape (storage media):
• Backing up and archiving, especially for large volumes of data
• High storage capacity (10TB), low cost
• Slow access time, sequential access.
• Magnetic storage
CD (storage data):
• Audio and data storage, software distributions
• Affordable, widely compatible.
• Low capacity (700 MB), susceptible to scratches.
• Optical storage.
DVD (storage device):
• High-capacity storage for data, video, and software distribution.
• Higher capacity than CD (8.5 GB), affordable
• Susceptible to scratches, lower capacity than blue-ray.
• Optical storage
Blue-ray (storage device):
• High -definition video and high-capacity data storage
• High-capacity (50 GB), high-resolution video storage
• More expensive, and requires specific hardware.
• Optical storage
Solid-state drive (SSD):
• Fast internal storage for modern company.
• Fast access time, no moving parts, high capacity (30TB)
• More expensive, limited write cycles.
• Solid-state storage
Portable solid-state drive:
• External storage for fast data transfer and backup
• Fast access time, portable, no moving parts, high capacity (2TB)
• More expensive, limited write cycles.
• Solid-state storage
USB memory stick:
• Portable data storage and transfer for various device.
• Small size, fast read/write speeds, high capacity (1 TB)
• Limited capacity compared to other storage devices.
• Solid-state storage.
Flash memory (SD/XD):
• Removeable memory cards used in smartphones / digital camera
• Very small, durable, large capacity
• Easy to lose due to size, expensive per GB compared to HDD
• Solid-state storage
Types of disks:
• ROM disk are read-only disks
• R disks can be written to once only
• RW disks can be written to many times
