Tashkent university of information technologies subject of operating systems

Conclusion
External storage devices are located in the computer system unit, as well as in its individual housings. External devices are usually called data storage devices. A storage device is a device that stores information for a long period of time. Their size is several hundred times larger than random access memory. A storage device can be thought of as a data carrier and a reader. There are two types of media: tape and disk. Tapes can only be magnetic, while disk carriers can be magnetic, magneto-optical and optical.

References:

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Websites used:
1. https://computer.howstuffworks.com/ram.htm
2. https://www.tutorialspoint.com/computer_fundamentals/computer_ram.htm