Digital

This originally means to express numbers with fingers. Digital and analog are defined as opposites&sbquo and the expression "discrete" is always used when defining digital. Discrete means something that was unified has become dispersed&sbquo and mathematically means "picking up values at a certain interval." When there is a minimal? unit such as a number of people or an amount of money&sbquo the integral multiples of that unit are the discrete values and that quantity is called the digital quantity. To? give a concrete example&sbquo the digital watch displays the time in digits as is&sbquo but the? analog watch indicates the hour&sbquo minute and second within a 12-hour flow. Another? example is the fluorescent light&sbquo which has a digital mechanism in which the fluorescent substance emits light through the instantaneous switching of the positive and negative poles. A regular light bulb emits light owing to high temperatures caused? by loading the filament with continuous voltage. This is an analog mechanism. Digital quantities are expressed by numbers or codes. Systems that handle calculation&sbquo memory&sbquo reproduction&sbquo transmission and display of digital quantities execute? logical computation&sbquo or data processing&sbquo through combinations of elements that only take discrete forms such as on-off switches&sbquo pulses or voltage. With analog data processing systems&sbquo it is only possible to make calculations within the physical law since there is the limitation of having to abide by physical combination of elements. The digital method&sbquo therefore&sbquo is more flexible in data processing. Analog quantities. however&sbquo can also generate accurate expression and display if the minimal quantity is properly defined. This is why conversions of analog quantities into digital quantities. and vice-versa&sbquo are made. These are called analog-digitaI (A-D) conversion and digital-analog (D-A) conversion.

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