# News tagged with number

## Surveillance is pervasive: Yes, you are being watched, even if no one is looking for you

The U.S. has the largest number of surveillance cameras per person in the world. Cameras are omnipresent on city streets and in hotels, restaurants, malls and offices. They're also used to screen passengers for the Transportation ...

## Researchers: Chinese-made GPS tracker highly vulnerable

A popular Chinese-made automotive GPS tracker used in 169 countries has severe software vulnerabilities, posing a potential danger to highway safety, national security and supply chains, cybersecurity researchers have found.

## Researchers reveal an unexpected feature of atomic nuclei when a 'magic' number of neutrons is reached

A curious thing happened when MIT researchers Adam Vernon and Ronald Garcia Ruiz, along an international team of scientists, recently performed an experiment in which a sensitive laser spectroscopy technique was used to measure ...

## 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