Semantics (computer science)

In programming language theory, semantics is the field concerned with the rigorous mathematical study of the meaning of programming languages. It does so by evaluating the meaning of syntactically legal strings defined by a specific programming language, showing the computation involved. In such a case that the evaluation would be of syntactically illegal strings, the result would be non-computation. Semantics describes the processes a computer follows when executing a program in that specific language. This can be shown by describing the relationship between the input and output of a program, or an explanation of how the program will execute on a certain platform, hence creating a model of computation.

Formal semantics, for instance, helps to write compilers, better understand what a program is doing and to prove, e.g., that the following if statement

has the same effect as S1 alone.

Overview

The field of formal semantics encompasses all of the following:

Information technology

Information technology (IT) is the application of computers and telecommunications equipment to store, retrieve, transmit and manipulate data, often in the context of a business or other enterprise. IT is considered a subset of information and communications technology (ICT). In 2012, Zuppo proposed an ICT hierarchy where each hierarchy level "contain some degree of commonality in that they are related to technologies that facilitate the transfer of information and various types of electronically mediated communications.". Business/IT was one level of the ICT hierarchy.

The term is commonly used as a synonym for computers and computer networks, but it also encompasses other information distribution technologies such as television and telephones. Several industries are associated with information technology, including computer hardware, software, electronics, semiconductors, internet, telecom equipment, engineering, healthcare, e-commerce and computer services.

Humans have been storing, retrieving, manipulating and communicating information since the Sumerians in Mesopotamia developed writing in about 3000 BC, but the term information technology in its modern sense first appeared in a 1958 article published in the Harvard Business Review; authors Harold J. Leavitt and Thomas L. Whisler commented that "the new technology does not yet have a single established name. We shall call it information technology (IT)." Their definition consists of three categories: techniques for processing, the application of statistical and mathematical methods to decision-making, and the simulation of higher-order thinking through computer programs.

Science (journal)

Science, also widely referred to as Science Magazine, is the peer-reviewed academic journal of the American Association for the Advancement of Science (AAAS) and one of the world's top academic journals. It was first published in 1880, is currently circulated weekly and has a print subscriber base of around 130,000. Because institutional subscriptions and online access serve a larger audience, its estimated readership is 570,400 people.

The major focus of the journal is publishing important original scientific research and research reviews, but Science also publishes science-related news, opinions on science policy and other matters of interest to scientists and others who are concerned with the wide implications of science and technology. Unlike most scientific journals, which focus on a specific field, Science and its rival Nature cover the full range of scientific disciplines. According to the Journal Citation Reports, Science's 2014 impact factor was 33.611.

Although it is the journal of the AAAS, membership in the AAAS is not required to publish in Science. Papers are accepted from authors around the world. Competition to publish in Science is very intense, as an article published in such a highly cited journal can lead to attention and career advancement for the authors. Fewer than 10% of articles submitted are accepted for publication.

Science (TV channel) (disambiguation)

Discovery Science Channel may refer to:

TV channels

Others

"I Love the World"
"I Hate the World"
"Discovery Toys"

See also (disambiguation) (Watch TV Below)

Science (disambiguation)

Science (from the Latin scientia, meaning "knowledge") usually describes the effort to understand how the universe works through the scientific method, with observable evidence as the basis of that understanding; a way of understanding the world through thought and experimentation. The sciences tend to be positivistic in their approach to truth and knowledge, in contrast to the humanities which tend toward relativism.

Historically and also in common use, the word "science" is often used as a shorthand for natural science, but other recognized science fields are social sciences, behavioral sciences, applied sciences and formal sciences - but not to humanities. "Science" may refer to any knowledge which has been reduced to an algorithmic system, and does not involve the need for an indescribable skill or mastery, such as a fine art. The general term art, and particularly the technical arts have some overlap with science, in this latter sense.

Disciplines referred to as "science":

Computer (disambiguation)

A computer is a program machine that receives input, stores and manipulates data, and provides output in a useful format.

Computer may also refer to:

Human computer

The term "computer", in use from the early 17th century (the first known written reference dates from 1613), meant "one who computes": a person performing mathematical calculations, before electronic computers became commercially available. "The human computer is supposed to be following fixed rules; he has no authority to deviate from them in any detail." (Turing, 1950) Teams of people were frequently used to undertake long and often tedious calculations; the work was divided so that this could be done in parallel.

The first time the term "Computer" appeared in The New York Times was February 3, 1853; an obituary stated:

Since the end of the 20th century, the term "human computer" has also been applied to individuals with prodigious powers of mental arithmetic, also known as mental calculators.

Origins in astronomy

The approach was taken for astronomical and other complex calculations. Perhaps the first example of organized human computing was by the Frenchman Alexis Claude Clairaut (1713–1765), when he divided the computation to determine timing of the return of Halley's Comet with two colleagues, Joseph Lalande and Nicole-Reine Lepaute.