Question

swap

Answer 1

https://en.wikipedia.org/wiki/Virtual_memory

Answer 2

A swap is just using you hard drive to extend your memory when overused.

Answer 3

Linux terminology for Virtual Memory which extends your systems physical RAM.

Answer 4

Swap is a filesystem on it's own drive partition, and can be extended with swap files on a regular partition. The name swap goes back before Unix. Microsoft is the only one who calls it paging because pages of memory are swapped out/in to/from the swap partition.