The difference between analog and digital signals?


If you look around in nature, signals are the mode of messaging and interaction among the plats,animals and other living organisms. We find animals and birds, sending messages to each other by making peculiar sounds and noises. Man has evolved from making sounds and signals unlike his ancestors to send messages through a much more complex way. There is the Analog Signal and the Digital Signal. But both Analog and digital signals are used effectively to convey messages.


What is an Analog  Signal?

A signal basically conveys a piece of quantified physical information. There are different signals, such as speech which is conveyed through sound, gestures conveyed through light. Our vision is analogous too as we see a continuous gradation of colors and shapes. In electrical signals , the signal is continuously variable or in small packets. A clock is an  analog signal. Its hands are continuously. When data storage is done by  transmitting a continuous stream by varying the signal strength or frequency to add data it is an analogous signal. Telephones work on radio waves which are analog signals. Computers work only on digital signals. Modems convert digital signals to analog from the computer to transmit them over telephone lines and at the other end the modem converts it back to digital signal for the computer to process it. VCR;s tapes are analog.


What is a Digital Signal?

Digital has been derived from the Latin word, "Digitus" which means  finger. It means everything can be described in terms of integer numbers. Digital processing is signals sent only in integer numbers. Digital signals uses discrete values. It is either a 0 or 1 not a continuous gradation like an anlaog signal. It cannot have a value between 0 and 1 such as a 0.35. Computers can process only in digital signals. CDs are Digital too


Is Digital better than Analog signals?

Every one of us is quite aware about the utility of signals. Signals or normal signs in day to day life are used to convey message or information. Similarly, analog signals and digital signals are used to transmit the information or data from one person to another or from one machine to another. Telephones, cellular services, computers, music all rely heavily on the efficiency in transmission of signal. The onset of computers and e-technology has replaced the analog signals and digital signals are used nowadays for transmitting signals because apart from being expensive analog signals are more prone to trouble as they get altered or distorted by severe noise. Whereas, digital signals are uniformed and different! Almost all electronic devices use digital signals because they retain accuracy in their shape and amplitude in all sorts of disturbances and give continuous signals without any intervals or breaks. Hence analog signals more or less have been completely replaced by digital signals.


What is the difference between Analog and Digital signals?

Both analog and digital signals are used in modern world for carrying information. Analog is a continuous electric signal whereas digital signal is a non continuous electrical signal. Analog constantly changes its amplitude or width even though it is continuously going in one direction while the digital signal changes its value instantly from zero to one without having the restriction of particular time period.

Analog signal is known to change the value continuously by making a change in the properties of variables like liquid levels, fluid pressures, current changes or electrical voltage. Digital signal always have discrete values. Variation in analog signal is due to time and follows non-direct electrical signal. The digital signal goes through the changes in individual steps and comprises of pulses and digits.

Analog signal carries real quantity and voice intensification due to which there is variation in electric current. Digital signals work on discrete values and are constant on one pulse till it changes from one digit to another. This makes digitals signals more reliable as compared to analog signals. Digital signals work on two amplitude levels which are termed as nodes and are based on low or high, 0 or 1, and true or false. These digital signals when sent to computers are interpreted by the computer in its own language to decode the message sent by the signals.

One of the most important differences between analog signals and digital signals is that analog signals are the duplicates of sound waves and hence have a tendency to catch electromagnetic waves due to which they present the message in distorted manner and also creates lot of noise. Whereas digital signals work on binary values and hence are more productive and reliable.


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