Encoders Absolute- They provide a peculiar output for every resolvable movement or shaft rotation. More interestingly, they do not lose their position once power get cut off, but instead provide absolute position upon power-up without any need of a home cycle or any shaft rotation.

There are certain parameters to be considered when specifying absolute rotary encoders and they are: absolute encoder resolution, positional accuracy, and maximum update rate. The number of bits used to encode the position is absolute encoder resolution. A higher number of bits indicate a finer resolution; however, higher resolution does not necessarily imply high accuracy. Position accuracy is the maximum error of a reading in arc seconds.