Encoder (position)
# Encoder (position)

An encoder is a sensor which turns a position into an electronic signal.

There are two forms:

* Absolute encoders give an absolute position value.
* Incremental encoders count movement rather than position. With detection of a datum position and the use of a counter, an absolute position may be derived.

The position may be measured as either linear or angular position

* Linear encoder, converts linear position to an electronic signal
* Rotary encoder, converts rotary position to an electronic signal
