A plastic sheet with a photosensitive emulsion that comes in various formats for still and video cameras. When exposed to light, plastic-based film creates an "analog" of the actual scene. Film was ...

The original telephone technology, which was introduced in the late 1800s. Analog phones convert sound (air vibrations) into analogous electrical frequencies. Many homes and small offices still use ...

A method of transmitting information using energy waves. It doesn't have discrete levels but is a continuously variable wave. Human voice for example is transferred by directly converting the sound ...