When talking about the type of signal that is interpolated by controllers or servo motors, it could be digital or analog.
Analog encoder uses signals of 1Vpp or 11 mcA. This principle is used both for linear and absolute encoders.
In fact, it is an absolute encoder with a 0-10 V signal at the output 4-20 mA; 0-5V; 0.5-4.5V; 0-20 mA; etc. The device is used to measure angle, tilt, linear position and displacement. They gained their distribution in industrial automation, now they are being actively replaced by encoders with digital signals. But analog sensors continue to hold their niche due to their high reliability, ease of signal processing, and unified dimensions.
An absolute analog encoder is similar in design to a conventional absolute or incremental rotary encoder. Consists of a bearing assembly, a board with electronics, a housing, a connector. As for a linear encoder with analog signals, it usually has a potentiometric, magnetostrictive, resistive, magnetic principle of operation. By the construction it could be an angle sensor with a cable drum; a profile or rod with a sensitive element, in which a useful signal arises when moving relative to the rod of a passive position sensor - a magnetic carriage (simple permanent magnet) or a multi-turn potentiometer mounted on a screw and nut.