From MEPIS Documentation Wiki
The /proc file only exists in memory and is an interface between the kernel and the devices running on the system, however it is a major part of the file system. It contains a lot of information about what is going on in your computer, and individual files in it may be tweaked to make adjustments to the way your kernel and devices interact with each other. When the ps command is used it is accessing the information from /proc. It has its own man page and more information can be found there.
Tweaking and using /proc
slow web connections
echo 0 > /proc/sys/net/ipv4/tcp_window_scaling