(Electronics) Of a circuit or device having an output that is proportional to the input; SYN. analog, linear.

See modem.

Data that is represented by continuous variations in some physical property, such as voltage, frequency, or pressure. Compare digital data transmission.

A computer that measures data varying continuously in value, such as speed or temperature.
A computer that represents information by variable quantities (e.g., positions or voltages); SYN. analogue computer.
Computing device that performs calculations through the interaction of continuously varying physical quantities, such as voltages (as distinct from the more common digital computer, which works with discrete quantities). An analog computer is said to operate in real time (corresponding to time in the real world), and can therefore be used to monitor and control other events as they happen.
Although common in engineering since the 1920s, analog computers are not general-purpose computers, but specialize in solving differential calculus and similar mathematical problems. The earliest analog computing device is thought to be the flat, or planispheric, astrolabe, which originated in about the 8th century.

In electronics, current or voltage that conveys or stores information, and varies continuously in the same way as the information it represents (compare digital signal). Analogue signals are prone to interference and distortion.
The bumps in the grooves of a vinyl record form a mechanical analog of the sound information stored, which is then is converted into an electrical analog signal by the record player's pick-up device.