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Computer programming or coding is the composition of sequences of instructions, called programs, that computers can follow to perform tasks. It involves designing and implementing algorithms, step-by-step specifications of procedures, by writing code in one or more programming languages. Programmers typically use high-level programming languages that are more easily intelligible to humans than machine code, which is directly executed by the central processing unit. Proficient programming usually requires expertise in several different subjects, including knowledge of the application domain, details of programming languages and generic code libraries, specialized algorithms, and formal logic.
Auxiliary tasks accompanying and related to programming include analyzing requirements, testing, debugging (investigating and fixing problems), implementation of build systems, and management of derived artifacts, such as programs' machine code. While these are sometimes considered programming, often the term software development is used for this larger overall process – with the terms programming, implementation, and coding reserved for the writing and editing of code per se. Sometimes software development is known as software engineering, especially when it employs formal methods or follows an engineering design process. (Full article...)
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JavaScript (/ˈdʒɑːvəskrɪpt/), often abbreviated as JS, is a programming language and core technology of the Web, alongside HTML and CSS. 99% of websites use JavaScript on the client side for webpage behavior.
Web browsers have a dedicated JavaScript engine that executes the client code. These engines are also utilized in some servers and a variety of apps. The most popular runtime system for non-browser usage is Node.js.
JavaScript is a high-level, often just-in-time compiled language that conforms to the ECMAScript standard. It has dynamic typing, prototype-based object-orientation, and first-class functions. It is multi-paradigm, supporting event-driven, functional, and imperative programming styles. It has application programming interfaces (APIs) for working with text, dates, regular expressions, standard data structures, and the Document Object Model (DOM). (Full article...) -
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Paul Gardner Allen (January 21, 1953 – October 15, 2018) was an American businessman, computer programmer, researcher, investor, film producer, explorer, and philanthropist. He is best known for co-founding Microsoft Corporation with his childhood friend Bill Gates in 1975, which helped spark the microcomputer revolution of the 1970s and 1980s. Allen was ranked as the 44th-wealthiest person in the world by Forbes with an estimated net worth of $20.3 billion at the time of his death in October 2018.
Allen quit from day-to-day work at Microsoft in early 1983 after a Hodgkin lymphoma diagnosis, remaining on its board as vice-chairman. He and his sister, Jody Allen, founded Vulcan Inc. in 1986, a privately held company that managed his business and philanthropic efforts. He had a multi-billion dollar investment portfolio, including technology and media companies, scientific research, real estate holdings, private space flight ventures, and stakes in other sectors. He owned the Seattle Seahawks of the National Football League and the Portland Trail Blazers of the National Basketball Association, and was part-owner of the Seattle Sounders FC of Major League Soccer. Under the helm of Allen, the Seahawks won Super Bowl XLVIII and made it to two other Super Bowls (XL and XLIX). In 2000 he resigned from his position on Microsoft's board and assumed the post of senior strategy advisor to the company's management team.
Allen founded the Allen Institutes for Brain Science, Artificial Intelligence, and Cell Science, as well as companies like Stratolaunch Systems and Apex Learning. He gave more than $2 billion to causes such as education, wildlife and environmental conservation, the arts, healthcare, and community services. In 2004, he funded the first crewed private spaceplane with SpaceShipOne. He received numerous awards and honors, and was listed among the Time 100 Most Influential People in the World in 2007 and 2008. (Full article...) -
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Microsoft is a multinational computer technology corporation. Microsoft was founded on April 4, 1975, by Bill Gates and Paul Allen in Albuquerque, New Mexico. Its current best-selling products are the Microsoft Windows operating system; Microsoft Office, a suite of productivity software; Xbox, a line of entertainment of games, music, and video; Bing, a line of search engines; and Microsoft Azure, a cloud services platform.
In 1980, Microsoft formed a partnership with IBM to bundle Microsoft's operating system with IBM computers; with that deal, IBM paid Microsoft a royalty for every sale. In 1985, IBM requested Microsoft to develop a new operating system for their computers called OS/2. Microsoft produced that operating system, but also continued to sell their own alternative, which proved to be in direct competition with OS/2. Microsoft Windows eventually overshadowed OS/2 in terms of sales. When Microsoft launched several versions of Microsoft Windows in the 1990s, they had captured over 90% market share of the world's personal computers.
As of June 30, 2015, Microsoft has a global annual revenue of US$86.83 billion (~$109 billion in 2023) and 128,076 employees worldwide. It develops, manufactures, licenses, and supports a wide range of software products for computing devices. (Full article...) -
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In computing, a linker or link editor is a computer system program that takes one or more object files (generated by a compiler or an assembler) and combines them into a single executable file, library file, or another "object" file.
A simpler version that writes its output directly to memory is called the loader, though loading is typically considered a separate process. (Full article...) -
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Node.js is a cross-platform, open-source JavaScript runtime environment that can run on Windows, Linux, Unix, macOS, and more. Node.js runs on the V8 JavaScript engine, and executes JavaScript code outside a web browser.
Node.js lets developers use JavaScript to write command line tools and for server-side scripting. The ability to run JavaScript code on the server is often used to generate dynamic web page content before the page is sent to the user's web browser. Consequently, Node.js represents a "JavaScript everywhere" paradigm, unifying web-application development around a single programming language, as opposed to using different languages for the server- versus client-side programming.
Node.js has an event-driven architecture capable of asynchronous I/O. These design choices aim to optimize throughput and scalability in web applications with many input/output operations, as well as for real-time Web applications (e.g., real-time communication programs and browser games). (Full article...) -
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The Antikythera mechanism (/ˌæntɪˈkɪθɪərə/ AN-tih-KIH-ther-ə) is an Ancient Greek hand-powered orrery (model of the Solar System), described as the oldest known example of an analogue computer used to predict astronomical positions and eclipses decades in advance. It could also be used to track the four-year cycle of athletic games similar to an Olympiad, the cycle of the ancient Olympic Games.
This artefact was among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera in 1901. In 1902, it was identified by archaeologist Valerios Stais as containing a gear. The device, housed in the remains of a wooden-framed case of (uncertain) overall size 34 cm × 18 cm × 9 cm (13.4 in × 7.1 in × 3.5 in), was found as one lump, later separated into three main fragments which are now divided into 82 separate fragments after conservation efforts. Four of these fragments contain gears, while inscriptions are found on many others. The largest gear is about 13 cm (5 in) in diameter and originally had 223 teeth. All these fragments of the mechanism are kept at the National Archaeological Museum, Athens, along with reconstructions and replicas, to demonstrate how it may have looked and worked.
In 2005, a team from Cardiff University used computer x-ray tomography and high resolution scanning to image inside fragments of the crust-encased mechanism and read the faintest inscriptions that once covered the outer casing. This suggests it had 37 meshing bronze gears enabling it to follow the movements of the Moon and the Sun through the zodiac, to predict eclipses and to model the irregular orbit of the Moon, where the Moon's velocity is higher in its perigee than in its apogee. This motion was studied in the 2nd century BC by astronomer Hipparchus of Rhodes, and he may have been consulted in the machine's construction. There is speculation that a portion of the mechanism is missing and it calculated the positions of the five classical planets. The inscriptions were further deciphered in 2016, revealing numbers connected with the synodic cycles of Venus and Saturn. (Full article...) -
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In computer science, an interpreter is a computer program that directly executes instructions written in a programming or scripting language, without requiring them previously to have been compiled into a machine language program. An interpreter generally uses one of the following strategies for program execution:- Parse the source code and perform its behavior directly;
- Translate source code into some efficient intermediate representation or object code and immediately execute that;
- Explicitly execute stored precompiled bytecode made by a compiler and matched with the interpreter's Virtual Machine.
Early versions of Lisp programming language and minicomputer and microcomputer BASIC dialects would be examples of the first type. Perl, Raku, Python, MATLAB, and Ruby are examples of the second, while UCSD Pascal is an example of the third type. Source programs are compiled ahead of time and stored as machine independent code, which is then linked at run-time and executed by an interpreter and/or compiler (for JIT systems). Some systems, such as Smalltalk and contemporary versions of BASIC and Java, may also combine two and three types. Interpreters of various types have also been constructed for many languages traditionally associated with compilation, such as Algol, Fortran, Cobol, C and C++. (Full article...) -
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Computer graphics deals with generating images and art with the aid of computers. Today, computer graphics is a core technology in digital photography, film, video games, digital art, cell phone and computer displays, and many specialized applications. A great deal of specialized hardware and software has been developed, with the displays of most devices being driven by computer graphics hardware. It is a vast and recently developed area of computer science. The phrase was coined in 1960 by computer graphics researchers Verne Hudson and William Fetter of Boeing. It is often abbreviated as CG, or typically in the context of film as computer generated imagery (CGI). The non-artistic aspects of computer graphics are the subject of computer science research.
Some topics in computer graphics include user interface design, sprite graphics, rendering, ray tracing, geometry processing, computer animation, vector graphics, 3D modeling, shaders, GPU design, implicit surfaces, visualization, scientific computing, image processing, computational photography, scientific visualization, computational geometry and computer vision, among others. The overall methodology depends heavily on the underlying sciences of geometry, optics, physics, and perception.
Computer graphics is responsible for displaying art and image data effectively and meaningfully to the consumer. It is also used for processing image data received from the physical world, such as photo and video content. Computer graphics development has had a significant impact on many types of media and has revolutionized animation, movies, advertising, and video games, in general. (Full article...) -
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In SQL, null or NULL is a special marker used to indicate that a data value does not exist in the database. Introduced by the creator of the relational database model, E. F. Codd, SQL null serves to fulfil the requirement that all true relational database management systems (RDBMS) support a representation of "missing information and inapplicable information". Codd also introduced the use of the lowercase Greek omega (ω) symbol to represent null in database theory. In SQL,NULL
is a reserved word used to identify this marker.
A null should not be confused with a value of 0. A null indicates a lack of a value, which is not the same thing as a zero value. For example, consider the question "How many books does Adam own?" The answer may be "zero" (we know that he owns none) or "null" (we do not know how many he owns). In a database table, the column reporting this answer would start out with no value (marked by null), and it would not be updated with the value zero until it is ascertained that Adam owns no books.
In SQL, null is a marker, not a value. This usage is quite different from most programming languages, where a null value of a reference means it is not pointing to any object. (Full article...) -
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In mathematics and computer science, an algorithm (/ˈælɡərɪðəm/ ⓘ) is a finite sequence of mathematically rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing calculations and data processing. More advanced algorithms can use conditionals to divert the code execution through various routes (referred to as automated decision-making) and deduce valid inferences (referred to as automated reasoning), achieving automation eventually. Using human characteristics as descriptors of machines in metaphorical ways was already practiced by Alan Turing with terms such as "memory", "search" and "stimulus".
In contrast, a heuristic is an approach to problem solving that may not be fully specified or may not guarantee correct or optimal results, especially in problem domains where there is no well-defined correct or optimal result. For example, social media recommender systems rely on heuristics in such a way that, although widely characterized as "algorithms" in 21st century popular media, cannot deliver correct results due to the nature of the problem.
As an effective method, an algorithm can be expressed within a finite amount of space and time and in a well-defined formal language for calculating a function. Starting from an initial state and initial input (perhaps empty), the instructions describe a computation that, when executed, proceeds through a finite number of well-defined successive states, eventually producing "output" and terminating at a final ending state. The transition from one state to the next is not necessarily deterministic; some algorithms, known as randomized algorithms, incorporate random input. (Full article...) -
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A programming language is a system of notation for writing computer programs.
Programming languages are described in terms of their syntax (form) and semantics (meaning), usually defined by a formal language. Languages usually provide features such as a type system, variables and mechanisms for error handling. An implementation of a programming language in the form of a compiler or interpreter allows programs to be executed, either directly or by producing what's known in programming as an executable.
Computer architecture has strongly influenced the design of programming languages, with the most common type (imperative languages—which implement operations in a specified order) developed to perform well on the popular von Neumann architecture. While early programming languages were closely tied to the hardware, over time they have developed more abstraction to hide implementation details for greater simplicity. (Full article...) -
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C (pronounced /ˈsiː/ – like the letter c) is a general-purpose computer programming language. It was created in the 1970s by Dennis Ritchie, and remains very widely used and influential. By design, C's features cleanly reflect the capabilities of the targeted CPUs. It has found lasting use in operating systems, device drivers, and protocol stacks, but its use in application software has been decreasing. C is commonly used on computer architectures that range from the largest supercomputers to the smallest microcontrollers and embedded systems.
A successor to the programming language B, C was originally developed at Bell Labs by Ritchie between 1972 and 1973 to construct utilities running on Unix. It was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. It has become one of the most widely used programming languages, with C compilers available for practically all modern computer architectures and operating systems. The book The C Programming Language, co-authored by the original language designer, served for many years as the de facto standard for the language. C has been standardized since 1989 by the American National Standards Institute (ANSI) and the International Organization for Standardization (ISO).
C is an imperative procedural language, supporting structured programming, lexical variable scope, and recursion, with a static type system. It was designed to be compiled to provide low-level access to memory and language constructs that map efficiently to machine instructions, all with minimal runtime support. Despite its low-level capabilities, the language was designed to encourage cross-platform programming. A standards-compliant C program written with portability in mind can be compiled for a wide variety of computer platforms and operating systems with few changes to its source code. (Full article...) -
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In computer programming, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence between the instructions in the language and the architecture's machine code instructions. Assembly language usually has one statement per machine instruction (1:1), but constants, comments, assembler directives, symbolic labels of, e.g., memory locations, registers, and macros are generally also supported.
The first assembly code in which a language is used to represent machine code instructions is found in Kathleen and Andrew Donald Booth's 1947 work, Coding for A.R.C.. Assembly code is converted into executable machine code by a utility program referred to as an assembler. The term "assembler" is generally attributed to Wilkes, Wheeler and Gill in their 1951 book The Preparation of Programs for an Electronic Digital Computer, who, however, used the term to mean "a program that assembles another program consisting of several sections into a single program". The conversion process is referred to as assembly, as in assembling the source code. The computational step when an assembler is processing a program is called assembly time.
Because assembly depends on the machine code instructions, each assembly language is specific to a particular computer architecture. (Full article...) -
Image 14Information technology (IT) is a set of related fields that encompass computer systems, software, programming languages and data and information processing and storage. IT forms part of information and communications technology (ICT). An information technology system (IT system) is generally an information system, a communications system, or, more specifically speaking, a computer system — including all hardware, software, and peripheral equipment — operated by a limited group of IT users, and an IT project usually refers to the commissioning and implementation of an IT system.IT systems play a vital role in facilitating efficient data management, enhancing communication networks, and supporting organizational processes across various industries. Successful IT projects require meticulous planning, seamless integration, and ongoing maintenance to ensure optimal functionality and alignment with organizational objectives.
Although humans have been storing, retrieving, manipulating, and communicating information since the earliest writing systems were developed, 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.
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 products or services within an economy are associated with information technology, including computer hardware, software, electronics, semiconductors, internet, telecom equipment, and e-commerce. (Full article...) -
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Ada is a structured, statically typed, imperative, and object-oriented high-level programming language, inspired by Pascal and other languages. It has built-in language support for design by contract (DbC), extremely strong typing, explicit concurrency, tasks, synchronous message passing, protected objects, and non-determinism. Ada improves code safety and maintainability by using the compiler to find errors in favor of runtime errors. Ada is an international technical standard, jointly defined by the International Organization for Standardization (ISO), and the International Electrotechnical Commission (IEC). , the standard, called Ada 2022 informally, is ISO/IEC 8652:2023.
Ada was originally designed by a team led by French computer scientist Jean Ichbiah of Honeywell under contract to the United States Department of Defense (DoD) from 1977 to 1983 to supersede over 450 programming languages used by the DoD at that time. Ada was named after Ada Lovelace (1815–1852), who has been credited as the first computer programmer. (Full article...)
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Image 1Stephen Wolfram is a British-American computer scientist, physicist, and businessman. He is known for his work in computer science, mathematics, and in theoretical physics.
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Image 2This image (when viewed in full size, 1000 pixels wide) contains 1 million pixels, each of a different color.
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Image 5A lone house. An image made using Blender 3D.
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Image 6Deep Blue was a chess-playing expert system run on a unique purpose-built IBM supercomputer. It was the first computer to win a game, and the first to win a match, against a reigning world champion under regular time controls. Photo taken at the Computer History Museum.
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Image 7A head crash on a modern hard disk drive
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Image 8An IBM Port-A-Punch punched card
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Image 9Ada Lovelace was an English mathematician and writer, chiefly known for her work on Charles Babbage's proposed mechanical general-purpose computer, the Analytical Engine. She was the first to recognize that the machine had applications beyond pure calculation, and to have published the first algorithm intended to be carried out by such a machine. As a result, she is often regarded as the first computer programmer.
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Image 11Output from a (linearised) shallow water equation model of water in a bathtub. The water experiences 5 splashes which generate surface gravity waves that propagate away from the splash locations and reflect off of the bathtub walls.
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Image 12Margaret Hamilton standing next to the navigation software that she and her MIT team produced for the Apollo Project.
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Image 13Partial view of the Mandelbrot set. Step 1 of a zoom sequence: Gap between the "head" and the "body" also called the "seahorse valley".
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Image 14A view of the GNU nano Text editor version 6.0
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Image 15Partial map of the Internet based on the January 15, 2005 data found on opte.org. Each line is drawn between two nodes, representing two IP addresses. The length of the lines are indicative of the delay between those two nodes. This graph represents less than 30% of the Class C networks reachable by the data collection program in early 2005.
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Image 16GNOME Shell, GNOME Clocks, Evince, gThumb and GNOME Files at version 3.30, in a dark theme
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Image 17Grace Hopper at the UNIVAC keyboard, c. 1960. Grace Brewster Murray: American mathematician and rear admiral in the U.S. Navy who was a pioneer in developing computer technology, helping to devise UNIVAC I. the first commercial electronic computer, and naval applications for COBOL (common-business-oriented language).
Did you know? - load more entries
- ... that Earth 300 has designed a climate research vessel that would include a molten salt reactor and a quantum computer?
- ... that the study of selection algorithms has been traced to an 1883 work of Lewis Carroll on how to award second place in single-elimination tournaments?
- ... that Brazilian computer science researcher and internet pioneer Tadao Takahashi negotiated with drug lords to install internet equipment in his country?
- ... that a "hacker" with blog posts written by ChatGPT was at the center of an online scavenger hunt promoting Avenged Sevenfold's album Life Is but a Dream...?
- ... that a pink skin for Mercy in the video game Overwatch helped raise more than $12 million for breast cancer research?
- ... that Rust has been named the "most loved programming language" every year for seven years since 2016 by annual surveys conducted by Stack Overflow?
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