Simple file to keep track of various terms that keep coming up across readings in systems and computer science.
Usually a piece of dedicated RAM/NVRAM built into a hard-disk or disk array controller that provides hardware caching and faster throughput for bursty writes.
Also known as memory barrier
Non-Volatile Random Access Memory. It is a type of memory that retains its information when power is turned off. "Flash Storage" is quintisential non-volatile memory. Write speed and durability are usually a concern when compared to other forms of memory.
AKA "Disk Cache" - not to be confused with "Disk Buffer".
A Page Cache is a cache for pages that are read from or written to secondary storage, anything that is not RAM, such as disks, network filesystems etc. It co-exists with regular application memory in RAM transparently, the operating system uses unsed poritions of the main memory for the page cache. It's used to speed up access to data/pages "on disk".
visual reference: IO Stack in the Linux Kernel