Secondary storage technology refers to the storage devices and media that can hold data unless it is deleted or overwritten. It is non-volatile storage because it retails data even when the computer is switched off or the device loses power. It is also known as secondary storage memory, external memory, or auxiliary memory.
Purpose of secondary storage
Unlike the primary storage that stores data for a short period (when the computer is turned on) the secondary storage in computer provides a backup data storage incase the primary data is lost when the computer is switched off or when the data is destroyed either as a result of the cyber attack, technical malfunction or any other risks.
The main examples of secondary storage devices include external hard drives, tape drives, USB flash drives, SD cards, DVD, CD, floppy diskette and solid-state drive.
These devices can store a variety of programs and applications in the secondary storage memory thus when data is lost in the primary data it can be retrieved from archival. It should be noted that not all computers require secondary storage. The embedded computers mostly do not use secondary storage because they control the physical operations of the machines that are integrated within to provide real-time computing and results. For example, computers that are connected with washing machines and heating systems do not need to save data when the power is switched off since the instructions that operate it are stored on reading Only Memory (RAM).
However, most secondary storage devices are required because they store data permanently and even when data is lost on primary data; it can be retrieved in the last saved version of the files. This data backup ensures the secondary data complements the primary data.
Types of Secondary memory
There are three type of secondary memory in a computer that users utilize in storing data. These are optical devices, magnetic storage media, and solid-state storage.
Optical storage devices use microscopic light called a laser that scans the spinning disc area. The disc surface area is subdivided into tracks with each particular one with several flats areas and hollows. The information is packaged and stored as a spiral pattern of pits and ridges representing a binary 0 and binary 1. The laser produces light on the disc surface, and the surface areas reflect the light while the pits diverse the laser beam. The sensor of the reflected light is denoted as a binary. The most common optical type of secondary storage memory are Compact Discs(CDS), Blu-ray Discs( BDs), and Digital Video Discs(DVDs.
The other type of secondary memory is solid-state is created by the use of silicon microchips where data is kept electronically in silicon chips called cells. It is within the cells, in which the binary data is stored in electrical current form through a transistor that contains on/off mode. Any secondary storage device has a memory known as flash memory where the data is stored. Most of the solid-state devices are used in digital cameras, tablets, mobile phones, or as USB Drives. Unlike the hard disk drives, solid-state devices are faster since the data is stored electronically. The advantage of this secondary storage in a computer is that they are portable and can include a password for better protection of the data.
The magnetic device stores data using a magnetized medium. The data involves a magnetized section of 1 and demagnetized areas of binary 0. The main examples of magnetic media include; magnetic tape, floppy disks, and hard disk drive. Secondary storage in computers is very essential because it helps in recovering the lost data from primary storage. Several machines such as computers, cameras, and Smartphone’s have ports that allow the integration of specific secondary devices but others can function with many. Therefore, using a secondary memory in computer or any other gadget can help in data back up, and enhancing security.