A buffer s a region of memory used to temporarily hold data while it is being moved from one place to another. Typically, the data is stored in a buffer as it is retrieved from an input device (such as a Mouse) or just before it is sent to an output device (such as Speakers). However, a buffer may be used when moving data between processes within a computer.
Unbuffered — Most PCs and workstations use unbuffered memory which is faster than registered memory.
Registered/Buffered — Registered or buffered modules delay all information transferred to the module by one clock cycle. This type of memory is primarily used in servers.
Fully buffered — Designed for next-generation servers, features an advanced memory buffer.