Secondary storage devices are used to store digital data and are typically non-volatile, meaning they retain the data even when the device is turned off. Here are some commonly used secondary storage devices and their definitions:

Hard Disk

A hard disk drive (HDD) is a data storage device that uses magnetic storage to store and retrieve digital data. It is typically used as the primary storage device in a computer and is capable of storing large amounts of data.

Magnetic Tape

Magnetic tape is a storage medium that uses a magnetic coating to store data. It is commonly used for long-term storage of large amounts of data, such as backups of computer systems.

Flash Drive

A flash drive, also known as a USB drive or thumb drive, is a small and portable storage device that uses flash memory to store data. They are commonly used for transferring data between computers or for storing and transporting data.

Memory Card

A memory card is a small and portable storage device that is commonly used in cameras, smartphones, and other electronic devices to store digital data. They use flash memory to store data and are available in various sizes.

Optical Disks

Optical disks use lasers to read and write data to a disk. There are three types of optical disks commonly used: CD (Compact Disc), DVD (Digital Versatile Disc), and Blu-ray. CDs can hold up to 700 MB of data, DVDs can hold up to 4.7 GB of data, and Blu-ray disks can hold up to 25 GB of data (or 50 GB for dual-layer disks).

Units of Storage

Bit

A bit is the smallest unit of digital data, representing either a 0 or 1.

Byte

A byte is a unit of digital information that consists of eight bits. It is commonly used to measure the size of files or the amount of storage space on a device.

Kilobyte (KB)

A kilobyte is equal to 1,024 bytes. It is commonly used to measure the size of small files or the amount of storage space on a device.

Megabyte (MB)

A megabyte is equal to 1,048,576 bytes (~1,000KB). It is commonly used to measure the size of larger files or the amount of storage space on a device.

Gigabyte (GB)

A gigabyte is equal to 1,073,741,824 bytes (~1,000MB). It is commonly used to measure the storage capacity of secondary storage devices such as hard disks and flash drives.

Terabyte (TB)

A terabyte is equal to 1,099,511,627,776 bytes (~1,000GB). It is commonly used to measure the storage capacity of larger secondary storage devices such as external hard drives or network-attached storage devices.