In general an encoder is a device that converts data from one format to another.

We classify linear and rotary encoders according to the type of movement.

The difference between incremental and absolute encoders can be seen as the difference between stopwatch and clock.

The resolution is the smallest movement detected by the encoder. It is measured differently depending on the type of encoder.

The accuracy is a measure of how close the output is to where it should be.

Repeatability is the maximum difference between different measurements taken at the same actual position.

Find definitions of technical encoder terminologies here.

A magnetoresistive sensor consists of a resistor made of magnetically sensitive alloy strips such as nickel iron (NiFe).

For rotary encoders, the terms singleturn and multiturn are used.