Difference between Analog and Digital
Some measurements can be represented as “analog”, others are represented as “digital”. What’s the difference between analog and digital?
The term “Digital”
The term “digital” refers to a discrete quantity. A discrete quantity can be the number of people in a room, the number of books in a library, or the number of cars in a parking lot, etc. See the digital clock (to the right of the image).
The digital systems have a very high importance in the modern technology, especially in the computer and in the automatic control systems.
Digital technology is used in several areas:
- Mechanical
- Electromechanical
- Hydraulic
- Pneumatic
- Electronics.
Digital technology is mainly used in the last two areas.
The Term “Analog”
The term “analog” refers to quantities or values that vary continuously with time. An analog signal can be a distance, a temperature, a speed, etc. An analog signal can change slowly or quickly (like a home audio system). See the analog clock (left side of the picture).
On a daily basis, time is displayed in analog form on clocks (needle clocks) and discreetly (digital) by digital displays.
In analog technology, it is very difficult to store, manipulate, compare, compute, and retrieve information exactly as it was stored. Instead, digital technology (computers, for example) can perform tasks very quickly, very accurately, very precisely, and without delay.
Digital electronics are used to perform many of the functions that were previously performed by analog electronics.
A very obvious example is the fact that today music is recorded and played on compact discs (CDs), DVDs, hard disks (HDD), pen drives, etc., which was previously converted from its original analog format to digital format. The equipment used to play music in a digital format is full of digital logic circuits.
On the contrary, the acetate discs (long play discs and 45 rpm discs) used a needle that moved on the disc to play the recorded music in an analog form. No one questions the quality of the digital format because it has an excellent sound.
You may be interested to know what a logic circuit is?
More Digital Tutorials
- What is the difference between Analog & Digital?
- What is a logic circuit?
- Digital logic levels (high, low, 1, 0)
- The truth table
- Boolean algebra
- Karnaugh Map (K-map)
- Binary number system
- Hexadecimal numbering system
- BCD code – binary coded decimal
- Gray code – Gray code table
- Aiken code – Excess 3 code
- AND gate
- NAND gate
- OR gate
- NOR gate
- NOT gate
- XOR gate
- How to build a NAND gate with transistors & diodes?
- OR & AND logic gates made with diodes
- The combinational circuit
- The sequential circuit
- JK Flip-Flop
- What is a binary decoder?
