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

Most Read This Week Tagged "Number"

Pete the Cat and the Missing Cupcakes: A Groovy Mystery Adventure with Pete and the Case of the Missing Cupcakes

Pete the Cat and His Four Groovy Buttons

Naked Statistics: Stripping the Dread from the Data

More most read this week tagged "number"...

Number Books

More number books...

Lists

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?

128 books — 9 voters

The Thirteenth Tale by Diane Setterfield

The Thirteen Problems by Agatha Christie

13 Little Blue Envelopes by Maureen Johnson

Lucky 13

635 books — 75 voters

Nothing but Numbers

1,449 books — 213 voters

Zero in the Title - Fiction

358 books — 32 voters

A Thousand Splendid Suns by Khaled Hosseini

The First Four Years by Laura Ingalls Wilder

Great books with numbers in their titles.

186 books — 24 voters

We Were Eight Years in Power by Ta-Nehisi Coates

Eight Is Great

459 books — 37 voters

Featured News & Interviews

Genre Report: What’s Going On in the World(s) of Romantasy This Year

Read »

Quotes Tagged “Number”

“ I count everything. Even numbers, odd numbers, multiples of 10. I count the ticks of the clock i count the tocks of the clock I count the lines between the lines on a sheet of paper. I count the broken beats of my heart I count my pulse and my blinks and the number of tries it takes to inhale enough oxygen for my lungs. I stay like this I stand like this I count like this until the feeling stops. Until the tears stop spilling, until my fists stop shaking, until my heart stops aching. There are n ...more ”
― Tahereh Mafi, Unravel Me

26 likes

“ Most people would have probably lost count around seven. This was, Harry knew from his extensive reading on logic and arithmetic, the largest number that most people could visually appreciate. Put seven dots on a page, and most people can take a quick glance and declare, “Seven.” Switch to eight, and the majority of humanity was lost. ”
― Julia Quinn, What Happens in London

8 likes

More quotes...