What is the difference between digital and analog?

Digital refers to information sent in terms of 0s and 1s as binary data. Analog is info sent as a representation of the data. The best example is a normal clockface which you read by looking at the hands as opposed to a digtial clock which display the numbers.

An Analog signal can also be digitized to look analog. Think of a playground slide or better yet a long slide at the amusement park, you slide down the slide in a smooth analog ride, from top to bottom, if this slide was digitized, it would be like sliding down a very long staircase hitting a bump every 12 inches.

Sliding down a set of stairs in the house is the digital version of sliding down the analog slide at the playground at an elementary school.

Digital Oscilloscopes can print a wave on the screen to represent and analog wave, its actually a wave that would look like a set of steps if expanded many times over instead of a smooth slide as on an Analog Oscilloscope of the old days, a true representation.

Just another way to think about it. As a zero (0) and a one (1), this is just an ON or an OFF signal, this is the origin of the digital signal, then came the bit, then the byte, a series of digital 0's and 1's to represent something bigger and more complex like the number on a calculator or the music on a CD recorded from the Original Beatles Master Vinyl Recording Analog archive.

To think of programming in the terms of 0's and 1's would be going all the way back to the transistor memory of the 1950's (maybe even earlier) but a computer chip of today, believe it or not, still does the same thing, but it really is not thought of in such simple terms anymore.

Actually, the hard disk drive in your PC is going back to this as we speak, from a rotating disc to a piece of solid state equipment such as a SD card or a Thumb Drive, all transistorized, taking away the mechanical failure rates of the HDD.

Duane,

Stay out of the Sushi- You are correct in that it has nothing to do with programming. It does have to do with the format and clarity of the transmitted signal and how the programmer wants to take the data and massage it.

You are colliding way to many terms. Analog signal properties re defined as showing movement from on position to another. Like a Sine Wave on an "O" scope. Leave it there for now.

Digitizing says here is a line that goes up and down in a path moving out to the right.

If I hang a scope on a digitized signal I will see only vertical lines, I will not see a smooth transition to an analog signal.

The wave forms you are alluding to are the effects of the digitising code, not the signal properties themselves. For example if I want to make sure I get a desired analog picture of how a second stage "PLUS" would be recorded, I would say, hey code, watch this input and see if you get 16 shakes of "+X", if you do draw this wave form. However, if you see less than 16 shakes, I want a steep drop off back to the axis point.

Now thrown in bit stuffing and freq modulations, amplitute modulations and you scope is now giving to a libraries worth of information once toy get the clocking infor correct.

It is not now nor will it ever be an one to one representation. Even an Anlog image of sigmal is modulated between the carrier and the signal being ninduced onto the carrier.

For further info, Analog - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Analog) & Digital - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Digital)