Analog is an adjective that describes any form of technology or data that is represented by continuously varying physical measures compared to discrete digital values. It is based on the conceptual ruler of one variable versus another. This type of technology has been used in a wide variety of applications, such as audio, radio, and television.
An analog signal is characterized by its boundless nature, meaning it can represent data with an infinite range of values. This contrasts digital technology, which often dives data into limited “on or off” states. Since digital data must be converted into analog before transmission, analog signals are often applied in communication and signal processing systems.
In the early days of computing, all data was analog. Computers used to use physical switches and dials to input information into the machine. Later on, these methods were replaced by digital techniques. This means that early computers were analog machines and used analog signals to communicate.
Analog signals can also be used within electronics systems, including, amplifiers, loudspeakers, and pressure detectors. They are generally used in everything from FM radio stations to digital-to-analog converters (DACs).
Speaking in the broadest terms, analog data is represented in a continuous stream of values, while digital data is shown in a discrete format with specific values. While analog offers a richer range of input and output possibilities, it is also more vulnerable to interference. Digital systems are more reliable and efficient which is why many industries now use them in place of analog.
Despite digital’s advantages, analog is still found in a wide range of everyday technologies and continues to evolve. Because it is less expensive and generally intuitive for humans to use, it will likely remain in use for the foreseeable future.