First-In First-Out buffer
From Computer History Wiki
A First-In First-Out buffer (usually given as FIFO) is a form of buffer in which data is inserted at one end, and removed from the other, so that the data is retrieved in the same order as it went in - hence the name.
FIFO buffers are found in both hardware and software; in the latter, they are usually implemented as ring buffers, to avoid the un-productive overhead of shifting data around as data is added and removed.
FIFO buffers are also used in serial communications, where a UART needs to receive more data without interrupting the CPU.
