Data buffer: Difference between revisions

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In [[computing]], a '''buffer''' is a region of [[Memory (computers)|memory]] used to temporarily hold output or input data, comparable to [[buffer (telecommunication)|buffers in telecommunication]]. The data can be output to or input from devices outside the [[computer]] or [[Process (computing)|processes]] within a computer. Buffers can be implemented in either hardware or software, but the vast majority of buffers are implemented in software. Buffers are used when there is a difference between the rate at which data is received and the rate at which it can be processed, or in the case that these rates are variable, for example in a printer [[spooler]].

Since computers operate in binary, at the lowest level, a single [[byte]] in memory could be considered a buffer for (usually) 8 [[bit]]s, and even a [[Processor register]] can be considered a buffer for 16 or 32 bits. In practisepractice however, a buffer is thought of as being a [[contiguous]] area of memory of a certain length, but normally greater than one.

[[Logical record]]s are often grouped into fixed length blocks (the "physical record"), to improve the efficiency of [[hard drive]]s. The memory allocated for these were often known as "file buffers" and provided a measure of [[asynchronous]] processing between [[cpu]] and [[hardware channel]] by using two or more in a "flip-flop" fashion.