Data buffer

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"Memory buffer" redirects here. It is not to be confused with memory buffer register.






Telecommunication buffer[edit]


Buffers are used for many purposes, including:

  • Interconnecting two digital circuits operating at different rates,
  • Holding data for later use,
  • Allowing timing corrections to be made on a data stream,

Buffer versus cache[edit]

A cache often also acts as a buffer, and vice versa. However, caches operate on the premise that the same data will be read from them multiple times, that written data will soon be read, or that there is a good chance of multiple reads or writes to combine to form a single larger block. Their sole purpose is to reduce accesses to the underlying slower storage. A cache is also usually an abstraction layer that is designed to be invisible.

A "Disk Cache" or "File Cache" keeps statistics on the data contained within it and commits data within a time-out period in write-back modes. A buffer does none of this.

A buffer is primarily used for input, output, and sometimes very temporary storage of data that is either en route between other media or data that may be modified in a non-sequential manner before it is written (or read) in a sequential manner.


  • The BUFFERS command/statement in CONFIG.SYS of DOS.
  • The buffer between a serial port (UART) and a MODEM. The COM port speed may be 38400 bit/s while the MODEM may only have a 14400 bit/s carrier.
  • The Framebuffer on a video card.


An early mention of a print buffer is the Outscriber devised by image processing pioneer Russel A. Kirsch for the SEAC computer in 1952:[1]


See also[edit]

