Digital and Analog are two different types of signals in nature. They are used to send data from the transmitter to the receiver. The Digital signal has 2 states HIGH and LOW. Whereas Analog is variable in nature and can change as per the factors involved.
Digital Signal
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Understanding the digital signal is like the switch being turned ON and OFF. A digital signal carries the data in the form of binary because it signifies in the bits i.e. 1’s and 0’s.
Digital is represented in many ways:
- ON / OFF
- 1 / 0
- HIGH / LOW
- TRUE / FALSE
- 3.3V / 0V
- 5V / 0V
When you group many digital bits/signal together you can form a binary integer. A group of 8 bits is called a byte. Computer data is organised in the form of bytes. This decimal representation is also used to represent voltage levels in microcontroller like Arduino, RPi etc
Analog Signal
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Now the digital signal is like the line drawn by a butterfly while flying. An analog signal is variable in nature and is one type of continuous time-varying signals, and these are classified into composite and simple signals. A simple type of analog signal is nothing but a sine wave, and that can’t be decomposed, whereas a composite type analog signal can be decomposed into numerous sine waves.
Arduino can take and give digital and analog signals as INPUT’s and OUTPUT’s.