"When your computer needs to run programs that are bigger than
your available physical memory, most modern operating systems use a
technique called swapping, in which chunks of memory are
temporarily stored on the hard disk while other data is moved into
physical memory space. Here are some techniques that may help you
better manage swapping on Linux systems and get the best
performance from the Linux swapping subsystem.
"Linux divides its physical RAM (random access memory) into
chucks of memory called pages..."