RAM stands for Random Access Memory. When you turn off your computer all data stored in the ram is deleted. The RAM is volatile

ROM- The ROM stands for Read-Only Memory. All data on the ROM can't be deleted and can only be read, this is why it is called the read only memory. Unlike the RAM the ROM isn't volatile.

Virtual Memory- Virtual memory combines your ram with temporary space on your hard disk. When ram runs low the virtual memory moves moves data from the RAM to a space called the paging file

Flash Memory- Flash memory is an electronic non-volatile computer storage medium that can be electrically erased and reprogrammed. It was introduced by Tobisha in 1984

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