Signal
1. A signal is an electromagnetic or electrical current that carries data from one system or network to another.
2. In electronics, a signal is an electric current or electromagnetic field used to convey data from one place to another.
In electronics, a signal is often a time-varying voltage that is also an electromagnetic wave carrying information, though it can take on other forms, such as current. There are two main types of signals used in electronics: analog and digital signals.
An analog signal is time-varying and generally bound to a range (e.g. +12V to -12V), but there is an infinite number of values within that continuous range. An analog signal uses a given property of the medium to convey the signal’s information, such as electricity moving through a wire. In an electrical signal, the voltage, current, or frequency of the signal may be varied to represent the information. Analog signals are often calculated responses to changes in light, sound, temperature, position, pressure, or other physical phenomena.
A digital signal is a signal that represents data as a sequence of discrete values. A digital signal can only take on one value from a finite set of possible values at a given time. With digital signals, the physical quantity representing the information can be many things:
• Variable electric current or voltage
• Phase or polarization of an electromagnetic field
• Acoustic pressure
• The magnetization of a magnetic storage media
Digital signals are used in all digital electronics, including computing equipment and data transmission devices.
Vedantu: Learn Live Online https://www.vedantu.com/physics/
Techopedia https://www.techopedia.com/definition/
Analog Signals vs. Digital Signals https://www.monolithicpower.com/en/analog-vs-digital-signal