Computer science

computer scientistcomputer sciencescomputer scientists
Computer science deals with the theoretical foundations of computation and practical techniques for their application.

Mathematical model

mathematical modelingmodelmathematical models
A mathematical model is a description of a system using mathematical concepts and language. The process of developing a mathematical model is termed mathematical modeling. Mathematical models are used in the natural sciences (such as physics, biology, earth science, chemistry) and engineering disciplines (such as computer science, electrical engineering), as well as in the social sciences (such as economics, psychology, sociology, political science).

Encapsulation (computer programming)

In object-oriented programming (OOP), encapsulation refers to the bundling of data with the methods that operate on that data, or the restricting of direct access to some of an object's components. Encapsulation is used to hide the values or state of a structured data object inside a class, preventing unauthorized parties' direct access to them. Publicly accessible methods are generally provided in the class (so-called "getters" and "setters") to access the values, and other client classes call these methods to retrieve and modify the values within the object.

Free and open-source software

free and open-sourcefree and open source softwareFOSS
Free and open-source software (FOSS) is software that can be classified as both free software and open-source software. That is, anyone is freely licensed to use, copy, study, and change the software in any way, and the source code is openly shared so that people are encouraged to voluntarily improve the design of the software. This is in contrast to proprietary software, where the software is under restrictive copyright licensing and the source code is usually hidden from the users.

Lock (computer science)

It is not appropriate for use in Web application development. Optimistic locking: this allows multiple concurrent users access to the database whilst the system keeps a copy of the initial-read made by each user. When a user wants to update a record, the application determines whether another user has changed the record since it was last read. The application does this by comparing the initial-read held in memory to the database record to verify any changes made to the record. Any discrepancies between the initial-read and the database record violates concurrency rules and hence causes the system to disregard any update request.

Online shopping

online retaileronline storeonline shop
Comparison of free software e-commerce web application frameworks. Dark store. Digital distribution. Electronic business. Online auction business model. Online music store. Online pharmacy. Online shopping malls. Online shopping rewards. Open catalogue. Personal shopper. Retail therapy. Self-publishing. Tourist trap. Types of retail outlets.

Online auction

Online auction business modelinternet auctiononline auctions
Web-based online commercial activity for online auctions dates back to 1995, when two auction sites were founded independently with alternative business models. The first online auction site was Onsale, founded by Jerry Kaplan in May 1995. In September that same year, eBay was founded by French-Iranian computer scientist Pierre Omidyar. Both of these companies used ascending bid. The Web offered new advantages such as the use of automated bids via electronic forms, a search engine to be able to quickly find items, and the ability to allow users to view items by categories.


Physics (from, from φύσις phýsis 'nature') is the natural science that studies matter, its motion and behavior through space and time, and that studies the related entities of energy and force. Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves.

General relativity

general theory of relativitygeneral relativity theoryrelativity
General relativity (GR), also known as the general theory of relativity (GTR), is the geometric theory of gravitation published by Albert Einstein in 1915 and the current description of gravitation in modern physics. General relativity generalizes special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time, or spacetime. In particular, the curvature of spacetime is directly related to the energy and momentum of whatever matter and radiation are present. The relation is specified by the Einstein field equations, a system of partial differential equations.

Quantum mechanics

quantum physicsquantum mechanicalquantum theory
Quantum mechanics, (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest – including atomic and subatomic – scales.

Lisp (programming language)

LispLisp programming languageLisp 1.5
Lisp (historically LISP) is a family of computer programming languages with a long history and a distinctive, fully parenthesized prefix notation. Originally specified in 1958, Lisp is the second-oldest high-level programming language in widespread use today. Only Fortran is older, by one year. Lisp has changed since its early days, and many dialects have existed over its history. Today, the best-known general-purpose Lisp dialects are Clojure, Common Lisp, and Scheme.

Capability-based security

Capability-based security is a concept in the design of secure computing systems, one of the existing security models. A capability (known in some systems as a key) is a communicable, unforgeable token of authority. It refers to a value that references an object along with an associated set of access rights. A user program on a capability-based operating system must use a capability to access an object. Capability-based security refers to the principle of designing user programs such that they directly share capabilities with each other according to the principle of least privilege, and to the operating system infrastructure necessary to make such transactions efficient and secure.

Packet switching

packet-switched networkpacket switchedpacket-switched
Packet switching is a method of grouping data that is transmitted over a digital network into packets. Packets are made of a header and a payload. Data in the header are used by networking hardware to direct the packet to its destination where the payload is extracted and used by application software. Packet switching is the primary basis for data communications in computer networks worldwide.

Multi-core processor

A multi-core processor is a computer processor integrated circuit with two or more separate processing units, called cores, each of which reads and executes program instructions, as if the computer had several processors. The instructions are ordinary CPU instructions (such as add, move data, and branch) but the single processor can run instructions on separate cores at the same time, increasing overall speed for programs that support multithreading or other parallel computing techniques. Manufacturers typically integrate the cores onto a single integrated circuit die (known as a chip multiprocessor or CMP) or onto multiple dies in a single chip package.

Mobile device

mobile deviceshandheldmobile
A mobile device (or handheld computer) is a computing device small enough to hold and operate in the hand. Typically, any handheld computer device will have an LCD or OLED flatscreen interface, providing a touchscreen interface with digital buttons and keyboard or physical buttons along with a physical keyboard. Many such devices can connect to the Internet and interconnect with other devices such as car entertainment systems or headsets via Wi-Fi, Bluetooth, cellular networks or near field communication (NFC). Integrated cameras, the ability to place and receive voice and video telephone calls, video games, and Global Positioning System (GPS) capabilities are common.

Responsive web design

responsive designresponsivemobile first
Responsive web design (RWD) is an approach to web design that makes web pages render well on a variety of devices and window or screen sizes. Recent work also considers the viewer proximity as part of the viewing context as an extension for RWD. Content, design and performance are necessary across all devices to ensure usability and satisfaction.

Operational semantics

operationalnatural semanticsOperationally
Operational semantics is a category of formal programming language semantics in which certain desired properties of a program, such as correctness, safety or security, are verified by constructing proofs from logical statements about its execution and procedures, rather than by attaching mathematical meanings to its terms (denotational semantics). Operational semantics are classified in two categories: structural operational semantics (or small-step semantics) formally describe how the individual steps of a computation take place in a computer-based system; by opposition natural semantics (or big-step semantics) describe how the overall results of the executions are obtained.

Massachusetts Institute of Technology

MITM.I.T.Massachusetts Institute of Technology (MIT)
Massachusetts Institute of Technology (MIT) is a private research university in Cambridge, Massachusetts. The Institute is a land-grant, sea-grant, and space-grant university, with an urban campus that extends more than a mile (1.6 km) alongside the Charles River. The Institute also encompasses a number of major off-campus facilities such as the MIT Lincoln Laboratory, the Bates Center, and the Haystack Observatory, as well as affiliated laboratories such as the Broad and Whitehead Institutes.

California Institute of Technology

CaltechCalifornia Institute of Technology (Caltech)Cal Tech
The California Institute of Technology (Caltech) is a private doctorate-granting research university in Pasadena, California. Known for its strength in natural science and engineering, Caltech is often ranked as one of the world's top-ten universities.

Kyoto University

Kyoto Imperial UniversityUniversity of KyotoKyoto
Kyoto University, or Kyodai is a national university in Kyoto, Japan. It is the second oldest Japanese university, one of Asia's highest ranked universities and one of Japan's National Seven Universities. One of Asia's leading research-oriented institutions, Kyoto University is famed for producing world-class researchers, including 19 Nobel Prize laureates, 2 Fields medalists and one Gauss Prize winner. It has the most Nobel laureates of all universities in Asia.

Microelectronics and Computer Technology Corporation

MCCM.E. MicroelectronicsMCC research consortium
Microelectronics and Computer Technology Corporation (Microelectronics and Computer Consortium - MCC) was the first, and at one time one of the largest, computer industry research and development consortia in the United States. MCC ceased operations in 2000 and was formally dissolved in 2004.

MIT Computer Science and Artificial Intelligence Laboratory

Project MACMIT Artificial Intelligence LaboratoryComputer Science and Artificial Intelligence Laboratory
MIT Computer Science and Artificial Intelligence Laboratory (CSAIL) is a research institute at the Massachusetts Institute of Technology formed by the 2003 merger of the Laboratory for Computer Science and the Artificial Intelligence Laboratory. Housed within the Stata Center, CSAIL is the largest on-campus laboratory as measured by research scope and membership.


Objective-C++Objective CCategory
Objective-C is a general-purpose, object-oriented programming language that adds Smalltalk-style messaging to the C programming language. It was the main programming language supported by Apple for the macOS, iOS and iPadOS operating systems, and their respective application programming interfaces (APIs) Cocoa and Cocoa Touch until the introduction of Swift in 2014.

SRI International

Stanford Research InstituteSRIStanford Research Institute (SRI)
SRI International (SRI) is an American nonprofit scientific research institute and organization headquartered in Menlo Park, California. The trustees of Stanford University established SRI in 1946 as a center of innovation to support economic development in the region.