Number

A number is a mathematical object used to count, measure, and label. The original examples are the natural numbers 1, 2, 3, and so forth. 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 (as with telephone numbers), for ordering (as with serial numbers), and for codes (as with ISBNs). In common usage, number may refer to a symbol, a word, or a mathematical abstraction.

In mathematics, the notion of number has been extended over the centuries to include 0, negative numbers, rational numbers, r A number is a mathematical object used to count, measure, and label. The original examples are the natural numbers 1, 2, 3, and so forth. 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 (as with telephone numbers), for ordering (as with serial numbers), and for codes (as with ISBNs). In common usage, number may refer to a symbol, a word, or a mathematical abstraction.

In mathematics, the notion of number has been extended over the centuries to include 0, negative numbers, rational numbers, real numbers such as √2 and π, and complex numbers, which extend the real numbers by adding a square root of −1. Calculations with numbers are done with arithmetical operations, the most familiar being addition, subtraction, multiplication, division, and exponentiation. Their study or usage is called arithmetic. The same term may also refer to number theory, the study of the properties of numbers.

Besides their practical uses, numbers have cultural significance throughout the world. For example, in Western society, the number 13 is regarded as unlucky, and "a million" may signify "a lot." Though it is now regarded as pseudoscience, numerology, the belief in a mystical significance of numbers, permeated ancient and medieval thought. Numerology heavily influenced the development of Greek mathematics, stimulating the investigation of many problems in number theory which are still of interest today.

During the 19th century, mathematicians began to develop many different abstractions which share certain properties of numbers and may be seen as extending the concept. Among the first were the hypercomplex numbers, which consist of various extensions or modifications of the complex number system. Today, number systems are considered important special examples of much more general categories such as rings and fields, and the application of the term "number" is a matter of convention, without fundamental significance. ...more

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Lists

YA Books With Numbers In The Title

47 books — 8 voters

Midnight in the Garden of Good and Evil by John Berendt

Cheaper by the Dozen by Frank B. Gilbreth Jr.

The Number Twelve

602 books — 33 voters

The Three Little Kittens by Marie Simchow Stern

Three is the Magic Number

562 books — 33 voters

Zero in the Title - Fiction

351 books — 31 voters

The Five People You Meet in Heaven by Mitch Albom

Book Titles That Begin With Numbers

266 books — 50 voters

The Vacancy in Room 10 by Seraphina Nova Glass

The Haunting of Room 904 by Erika T. Wurth

The Book in Room 316 by ReShonda Tate Billingsley

Room Service?

126 books — 9 voters

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Quotes Tagged “Number”

“ Seven, Richie thought. That's the magic number. There has to be seven of us. That's the way it's supposed to be. ...more ”
― Stephen King, It

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“ In democracy, quality means quantity; it is not about what kind of people gather around an idea, but how many. Similarly, it's not how deep the idea is, but how many it attracts. ...more ”
― Sov8840

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