What is different between digital and analog?

Answer 1

Consider this:

You want so signal your friend using a torch light. Now you might think there is only one way to signal to your friend by turning on and off the flashlight right? But actually there are more ways.

1) Turning on and off the flashlight

2) Dimming the torchlight and bringing it back to full shine

So here method 1) is the digital way to signal to your friend and method 2) is the analog way to signal to your friend.

Difference: In method one its either full signal or null as in case of digital signal 0 or 1

In method two there is always signal(torch is always glowing) but we are signaling by dimming the glow of light.

cheers,

...kam

In electronics, the term "digital" refers to circuits in which individual data are represented by a discrete set of voltages -- usually only two (i.e., either a "logic 1" or a "logic 0"). In this case, each datum is a binary entity called a bit. Data in the form of numbers other than 0 or 1 (e.g., 2, 365, 3.14159, etc.) are represented as patterns of bits.

In analog circuits, each datum is encoded as a continuous voltage within a range. Such circuits are widely used in such application areas as audio electronics, radio, motor control, etc.

Historically (c. 1960), analog computers were developed that competed with digital computers. However, digital circuits are at the heart of virtually all modern computers.

Answer 2

The difference between analog and digital has to do with the way data is transmitted. Both forms of data, whether it be a radio, a television, a phone, a cell phone, even a computer monitor can either be a conduit for receiving, or sending and receiving in the case of phones, either an analog or digital signal or data stream. Analog is the oldest form of data transfer. By shear definition, there is no telling when the first use of an analog transmission was first used. One demonstration of an analog signal is taking a string and tying either end to an empty tin can, then two people walk away from one another until the string is taught. Then while one person holds their end up to their ear, the other can talk to them simply by speaking into their empty can. However, this will only work for a short distance, and if the line is not kept taught then the signal fails. This works because unseen to the human eye, sound travels in waves, therefore the string acts as a device to capture the sound coming out of a tin can, or anything else that focuses the sound. The same goes for what is on the receiving end, it too has to have a shape that will focus the sound, except on the receiving end it is called resonating. The reason a device such as this has such limited range is somewhat obvious if you think about it. Due to the effects of interference, and something called amplification, gives two tin cans and a piece of string about a three to five meeter maximum effective analog signal. Introduce electricity and some electronic technology and pretty soon you can send an analog signal to the moon. And don't get the term electronics mixed with digital, even though you wouldn't have digital without electronics, there is a big difference. Contrary to what many people have thought when the first personal computers came out with an actual display, before that all pc's only had switches and lights, and with the exception of a Xerox prototype, it wouldn't be until Stephen Wozniak, co founder of Apple Computer, patented the first digital to analog device for using a regular analog television for use with the Apple computer. Prior to then you either had to buy a specially designed monitor that would properly read the digital signal coming from the computer. It would be another two decades of pure digital to analog before the computer industry would switch to digital monitors. There are still an untold number of lcd monitors that people have to use an adapter in order to connect their analog monitor to a digital video card.

So what is digital? Digital by definition is anything that can either read or write in ones and zeros. In relationship to a signal; digital is delivered by coaxial cable, copper wires, micro waves, an infrared beam of light, radio waves of any range, and by laser fiber optic cable. All of which, with the exception of fiber optics, were originally designed to carry analog signals. So how do you know if you are reading this on a digital monitor, or if your cell phone or house phone is analog or digital. If the cable that plugs into your monitor goes into a receptacle that has three rows of holes and is kind of D shaped, that is analog. If it has a receptacle with holes and a slot for a flat piece of metal that matches up with the end of the cable, you have digital. Or if you happen to have a flat screen TV hooked up to your video card then that would be digital. Cell phones are all digital now but at one time they were analog. Your home phone is a bit tricky, more than likely it is analog. Only the very rich can afford a digital home phone system, but as the progression of fiber optics becomes available to more and more home users then all phones will go digital. If you have a cable phone or one of those devices that uses your computer as a way to use a phone. That is the same thing as watching TV on an analog set but the signal is converted from digital to analog. So if you have a TV that isn't a flat screen then it is very doubtful you have a digital TV, even though it may be rated as an HD or Hi-Def TV, if it is shooting a cathode rayed tube (CRT), then it is most likely an analog signal. Even some of the early LCD TV's were analog.