Analog and Digital......

The difference between analog and digital is very simple. When something is digital it only has two states, for example on and off. With analog you have a range. Let me give you two examples.

1. Imagine a car. Cars have an analog input (for example the throttle). Let's say your car can go 100 mph. Your car starts standing, or it's moving at 0 mph. When you press the gas, your car accelerates 1, 2, 3, 4, 5...50..100 mph. Depending on your hard you press the gas you will go a different speed. Now let's think of a digital car. This car only has two speeds, for example 0 and 100 mph. At zero your car is still standing but now when you press the gas, no matter how hard, you will automatically be going 100 mph. With digital you only have two choices but with analog you can choose to drive 50 if you'd like by pressing the gas half way.

2. Light switch. There are two kinds of light switches so this one might be a better example. The most common light switch either turn the light on or off. These are digital switches. If you have a dimmer light switches in your house you don't have to set your lights to the max. You can set it half way and the lights will only be half as bright as they would be at the maximum level. This is analog control.

Imagine a car

Except...that you might have noticed that some car operators are more prone to drive analog (mostly experienced males) while others are more prone to drive digital (mostly females)--an exceptional, special case being pre-analog-phase young males, where digital is defined as foot-on-brake-pedal (a "real" zero state) or gas pedal to the floor (a (socio-ana)logical high state).

(In similar fashion, automatic transmissions tend to be found in digitally-operated cars, manual transmissions in analogically-operated. You can tell which by observing vehicle tail light indicators.)

You should pitch this theory to a psychology major who is looking for a research topic. It would also be nice to know the effects of automatic transmission on reaction times.

Thanks but, alas, said thesis seeker's need for departmental approval dissuades me from making the pitch. And the difficulty of devising a double-blind study presents a formidable obstacle of its own.

My hypothesis would be a tendency towards under-reaction times--both the operator (who's more likely to be lulled) and the vehicle (with the additional mass to be accelerated or slowed).

Digital..like your digits (fingers) for counting 1,2,3,4,5 Analogue to give an analogy (ho ho) smooth and continuous like filling a glass of beer by pouring into it, you can have an infinite variation of fullness.

The Digital glass filler might have just two or three levels of fullness, 'regular' 'thirsty' and 'just a bit I'm driving' with no allowable variation in between.

Generally (very generally...don't jump on me guys)

Digital systems are controlled by microcontrollers or computers (or presumably your fingers! joke)

Anlogue systems are general controlled by other circuits, variable resitors resitor/capacitor timers, photocells and suchlike or mechanical means, say levers..

As the previous respondent said...a car throttle is usually either a variable resistor (analoge) feeding and electronic controller, which converts this into a digital signal e.g. Probably a number between 0 and 255.

Or it's an old fashioned butterfly valve on and air-intake on a carburettor (anaolgue).

A Joystick is a typical source of an analog signal = resistance. ohm.

Because the computer cannot handle analogue data the signal had to be converted to digital. (ATD converter)

The games port (or at least in the early days of XT,AT or 386) assisted with the conversion.

A voltage were supplied over the resistor and the time required to decay to zero were counted.

typically the difference of 10 ohm resulted in a digital output of 0 to 100.

This output could then be scaled to the screen or whatever.

Guest:

An analog parameter varies continuously and has an infinite (theoretically) number of values, like the position of the accelerator pedal on your car. A digital parameter varies in steps or increments and cannot have a value between the steps. The steps can be made as small as you wish so that the parameter "seems" smooth, but can stilll only have a fixed number of values.

The world was mostly analog until computers came along and made it more desireable to work with a binary numbering system in which the possible number of steps is determined by the number of bits assigned to represent the possible range of the parameter.

DickL

Dick, don't forget analogue computers were around long before digital ones were...

Analogue = real world of infinite variables.

Digital = discrete steps only, as Del said digits of your hand for example.

John

I'm glad we havn't descended to the Digit/Anal jokes.

yet?

There's plenty of time left and let's face it it is FRIDAY afternoon (in the UK)....

John.

But what about the Jacquard loom...considered the first devise eventually giving rise to the electronic computer? The germinal invention from which current-age computers descended. Nothing analog about that I would think. What do you think?

Or the Babbage engine.... that's often thought of as the first 'computer' type device, but it works on a system of gearing and so is analogue, even though the results and the gear steps are of a digital nature.....

John ???

I wonder if they ever met, in the flesh. And how either might have answered the question.

http://www.maxmon.com/1800ad.htm

Why u people talk on central matter in brief. What's the need to make it so long with unnecessary word keys.

Why do you use u instead of you?

You are deleting parts of your message and making it almost incomprehensible to others, so why do you do it?