A special elemental magic

A staple in every science classroom is the periodic table of elements, and for many it is their first introduction to the vast mysteries of the natural world.

Brexit changed people's perception of immigrants for the better

New research by academics from four Universities including the University of Birmingham has found that anti-immigrant attitudes in the UK softened immediately following the Brexit referendum of 2016, among both Leave and ...

An inmate's love for math leads to new discoveries

There are many examples of mathematical breakthroughs achieved in prison. Maybe the most famous is from the French mathematician Andre Weil, who came up with his hugely influential conjectures while in a military prison in ...

How small chromosomes compete with big ones for a cell's attention

From avocado plants to baker's yeast, humans to zebras, sexually reproducing organisms must create germ cells that contain half the number of chromosomes found in a typical body cell. When these germ cells—such as sperm ...

Why smartphones are digital truth serum

Researchers from University of Pennsylvania published a new paper in the Journal of Marketing that explains that the device people use to communicate can affect the extent to which they are willing to disclose intimate or ...

Mathematical curves predict evolution in COVID-19 spread

Efforts to contain the spread of the Covid-19 pandemic are now the top priority of governments across the globe. As they make these life-saving decisions, it is particularly crucial for policymakers to accurately predict ...

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Number

A 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 (telephone numbers), for ordering (serial numbers), and for codes (e.g., ISBNs).

In common use, the word number can mean the abstract object, the symbol, or the word for the number.

This text uses material from Wikipedia, licensed under CC BY-SA