In
electronics terminology, a
buffer is a two terminal device, (one
input and one
output). It has no
logical effect on the
input signal, it simply passes it through to the
output. In this sense, it can be viewed as a non-inverting
inverter.
The buffer is used to "beef up" the output signal from a driver which has a high fanout, i.e. heavily loaded. A heavily loaded output driver will not be able to supply enough current to drive all the inputs connected to it, and signal deterioration, in the form of slew and skew problems, will occur if buffering is not used.
A common use for buffers in electronics is as a clock tree buffer.