Analog vs digital: what’s the difference?

Analog and digital signals are used to transmit information, such as audio or video, via electric signals. The main difference between the two is that in analog technology, information is translated into electric pulses of varying amplitude, and in digital technology, translation of information is into binary format (zero or one), where each bit is representative of two amplitudes. Read on below for more detail about each of these technologies.

Analog

People accept digital devices easily, often by thinking of them as electronic, computerized, or not even worth trying to understand. But the concept of analog technology often comes off as more mind-boggling, so what’s it all about?

If you have an analog watch, for example, it tells the time with hands that move around a dial, the position of the hands being a measurement of time. How much the hands move is directly related to what time it is. If the hour hand sweeps across two segments of the dial, it shows that twice as much time has passed compared to if it moved one segment. This sounds obvious, but it’s more subtle than it first appears, since the hand’s movements over the dial are a way of representing passing time. Basically, it’s not the same thing as time itself, but a representation or an analogy of time. This is really what the term “analog” means.

Up until computers began to dominate science and technology in the early 20^th century, virtually every measurement was analog. If you wanted to measure an electric current, you did so with a moving-coil meter that was equipped with a pointer moving over a dial. The quicker the pointer moved up the dial, the higher the current in your circuit, with the pointer being an analogy of the current. All kinds of measuring devices operated in a similar way, from speedometers and weighing machines to sound-level meters and seismographs.

But analog technology isn’t just about measuring things using dials and pointers. When someone says something is analog, it simply means it’s not digital: the job it performs or the information it handles doesn’t involve processing numbers electronically. For example, an old-style film camera is sometimes referred to as analog technology. It’s able to capture an image on a piece of plastic film coated with silver-based chemicals, which react to light. When the film is developed, it’s used to print a representation of the scene the user has photographed. Basically, the picture is an analog of the recorded scene.

Digital

Digital technology is entirely different from analog technology. Instead of storing words, pictures, and sounds as representations on materials such as magnetic tape or plastic film, the information is first converted into numbers (digits) that are displayed or stored.  

These days, most devices work using digital rather than analog technology. Smartphones, which most of us can relate to, transmit and receive calls by converting the sound of a person’s voice into numbers and then sends the numbers from one place to another in the form of radio waves. Because it can be used in such a way, digital technology has many advantages. It’s easier to store information in digital form and generally, it takes up less space. If you look at it the other way, you’d need several shelves to store 400 vinyl, analog LP records.

Digital information is also typically more secure. Smartphone conversations are encrypted before transmission, which is easy to do when information is in numeric form from the start. Another advantage is that users can edit and play with digital information without any hassle.

Which is better, analog or digital?

Just because digital technology has its advantages doesn’t mean it’s always better than analog. An analog watch might be much more accurate than a digital one if it uses a high-precision movement to measure passing time. Generally, the most expensive watches in the world are analog ones, though the world’s most accurate atomic clocks show time with digital displays.

But will information stored in digital form last as long as analog information? Museums are filled with paper documents, and ones written on store or clay, that date back thousands of years, but no one has the first email or cellphone conversation saved. If you open a history book on photography you’ll find reproductions of the earliest photos, but you won’t see any pictures of the first digital photo.

Although digital technology will likely dominate the future, analog technology will always have its place.

Source: explainthatstuff.com