數學知識交流(6)----digital vs number

DigitalA digital system[1] is a data technology that uses discrete (discontinuous) values. By contrast, non-digital (or analog) systems use a continuous range of values to represent information. Although digital representations are discrete, the information represented can be either discrete, such as numbers, letters or icons, or continuous, such as sounds, images, and other measurements of continuous systems.The word digital comes from the same source as the word digit and digitus (the Latin word for finger), as fingers are used for discrete counting. It is most commonly used in computing and electronics, especially where real-world information is converted to binary numeric form as in digital audio and digital photography.NumberA number is a mathematical object used to count and measure. In mathematics, the definition of number has been extended over the years to include such numbers as zero, negative numbers, rational numbers, irrational numbers, and complex numbers.Mathematical operations are certain procedures that take one or more numbers as input and produce a number as output. Unary operations take a single input number and produce a single output number. For example, the successor operation adds one to an integer, thus the successor of 4 is 5. Binary operations take two input numbers and produce a single output number. Examples of binary operations include addition, subtraction, multiplication, division, and exponentiation. The study of numerical operations is called arithmetic.A notational symbol that represents a number is called a numeral. In addition to their use in counting and measuring, numerals are often used for labels , for ordering, and for codes.In common use, the word number can mean the abstract object, the symbol, or the word for the number.I dont know the answer but i found thismaybe you can find out the answer in these websiteshttp://en.wikipedia.org/wiki/Digitalhttp://en.wikipedia.org/wiki/Number