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.

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

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

Find definitions of technical encoder terminologies here.

With a variety of outputs, reading types and encoder body options to choose from, how can one get the best sensor for his application?

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