Portal:Computer programming

Programming languages are used for controlling the behavior of a machine (often a computer). Like natural languages, programming languages follow rules for syntax and semantics.

There are thousands of programming languages and new ones are created every year. Few languages ever become sufficiently popular that they are used by more than a few people, but professional programmers may use dozens of languages in a career.

Most programming languages are not standardized by an international (or national) standard, even widely used ones, such as Perl or Standard ML (despite the name). Notable standardized programming languages include ALGOL, C, C++, JavaScript (under the name ECMAScript), Smalltalk, Prolog, Common Lisp, Scheme (IEEE standard), ISLISP, Ada, Fortran, COBOL, SQL, and XQuery. (Full article... )

C# (/ˌsiːˈʃɑːrp/ see SHARP) is a general-purpose high-level programming language supporting multiple paradigms. C# encompasses static typing, strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented (class-based), and component-oriented programming disciplines.

The principal designers of the C# programming language were Anders Hejlsberg, Scott Wiltamuth, and Peter Golde from Microsoft. It was first widely distributed in July 2000 and was later approved as an international standard by Ecma (ECMA-334) in 2002 and ISO/IEC (ISO/IEC 23270 and 20619) in 2003. Microsoft introduced C# along with .NET Framework and Microsoft Visual Studio, both of which are technically speaking, closed-source. At the time, Microsoft had no open-source products. Four years later, in 2004, a free and open-source project called Mono began, providing a cross-platform compiler and runtime environment for the C# programming language. A decade later, Microsoft released Visual Studio Code (code editor), Roslyn (compiler), and the unified .NET platform (software framework), all of which support C# and are free, open-source, and cross-platform. Mono also joined Microsoft but was not merged into .NET.
As of April 2025,^[update] the most recent stable version of the language is C# 14. (Full article... )

Erlang (/ˈɜːrlæŋ/ UR-lang) is a general-purpose, concurrent, functional high-level programming language, and a garbage-collected runtime system. The term Erlang is used interchangeably with Erlang/OTP, or Open Telecom Platform (OTP), which consists of the Erlang runtime system, several ready-to-use components (OTP) mainly written in Erlang, and a set of design principles for Erlang programs.

The Erlang runtime system is designed for systems with these traits:

• Distributed
• Fault-tolerant
• Soft real-time
• Highly available, non-stop applications
• Hot swapping, where code can be changed without stopping a system.

(Full article... )

Charles Babbage KH FRS (/ˈbæbɪdʒ/ ; 26 December 1791 – 18 October 1871) was an English polymath. A mathematician, philosopher, inventor and mechanical engineer, Babbage originated the concept of a digital programmable computer.

Babbage is considered by some to merit the title of "father of the computer". He is credited with inventing the first mechanical computer, the difference engine, that eventually led to more complex electronic designs, though all the essential ideas of modern computers are to be found in his analytical engine, programmed using a principle openly borrowed from the Jacquard loom. As part of his computer work, he also designed the first computer printers. He had a broad range of interests in addition to his work on computers, covered in his 1832 book Economy of Manufactures and Machinery. He was an important figure in the social scene in London, and is credited with importing the "scientific soirée" from France with his well-attended Saturday evening soirées. His varied work in other fields has led him to be described as "pre-eminent" among the many polymaths of his century.

Babbage, who died before the complete successful engineering of many of his designs, including his Difference Engine and Analytical Engine, remained a prominent figure in the ideating of computing. Parts of his incomplete mechanisms are on display in the Science Museum in London. In 1991, a functioning difference engine was constructed from the original plans. Built to tolerances achievable in the 19th century, the success of the finished engine indicated that Babbage's machine would have worked. (Full article... )

Prolog is a logic programming language that has its origins in artificial intelligence, automated theorem proving, and computational linguistics.

Prolog has its roots in first-order logic, a formal logic. Unlike many other programming languages, Prolog is intended primarily as a declarative programming language: the program is a set of facts and rules, which define relations. A computation is initiated by running a query over the program.

Prolog was one of the first logic programming languages and remains the most popular such language today, with several free and commercial implementations available. The language has been used for theorem proving, expert systems, term rewriting, type systems,, automated planning,, and question answering as well as its original intended field of use, natural language processing. (Full article... )

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... )

Python is a high-level, general-purpose programming language. Its design philosophy emphasizes code readability with the use of significant indentation.

Python is dynamically type-checked and garbage-collected. It supports multiple programming paradigms, including structured (particularly procedural), object-oriented and functional programming.

Guido van Rossum began working on Python in the late 1980s as a successor to the ABC programming language. Python 3.0, released in 2008, was a major revision and not completely backward-compatible with earlier versions. Recent versions, such as Python 3.13, 3.12 and older (and 3.14), have added capabilities and keywords for typing (and more; e.g. increasing speed); helping with (optional) static typing. Currently only versions in the 3.x series are supported. (Full article... )

Augusta Ada King, Countess of Lovelace (née Byron; 10 December 1815 – 27 November 1852), also known as Ada 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 recognise that the machine had applications beyond pure calculation. Ada Lovelace is sometimes considered to be the first computer programmer.

Ada Lovelace was the only legitimate child of poet Lord Byron and reformer Anne Isabella Milbanke. All her half-siblings, Lord Byron's other children, were born out of wedlock to other women. Lord Byron separated from his wife a month after Ada was born and left England forever. He died in Greece whilst fighting in the Greek War of Independence, when she was eight. Lady Byron was anxious about her daughter's upbringing and promoted Lovelace's interest in mathematics and logic in an effort to prevent her from developing her father's perceived insanity. Despite this, Lovelace remained interested in her father, naming one son Byron and the other, for her father's middle name, Gordon. Upon her death, she was buried next to her father at her request. Although often ill in her childhood, Lovelace pursued her studies assiduously.

She married William King in 1835. King was already a Baron, and was created Viscount Ockham and 1st Earl of Lovelace in 1838. The name Lovelace was chosen because Ada was descended from the extinct Baron Lovelaces. The title given to her husband thus made Ada the Countess of Lovelace. (Full article... )

D , also known as dlang, is a multi-paradigm system programming language created by Walter Bright at Digital Mars and released in 2001. Andrei Alexandrescu joined the design and development effort in 2007. Though it originated as a re-engineering of C++, D is now a very different language. As it has developed, it has drawn inspiration from other high-level programming languages. Notably, it has been influenced by Java, Python, Ruby, C#, and Eiffel.

The D language reference describes it as follows: (Full article... )

The Antikythera mechanism (/ˌæntɪkɪˈθɪərə/ AN-tik-ih-THEER-ə, US also /ˌæntaɪkɪˈ-/ AN-ty-kih-) is an ancient Greek hand-powered orrery (model of the Solar System). It is the oldest known example of an analogue computer. It could be 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.

The artefact was among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera in 1901. In 1902, during a visit to the National Archaeological Museum in Athens, it was noticed by Greek politician Spyridon Stais as containing a gear, prompting the first study of the fragment by his cousin, Valerios Stais, the museum director. The device, housed in the remains of a wooden-framed case of (uncertain) overall size 34 cm ×ばつ 18 cm ×ばつ 9 cm (13.4 in ×ばつ 7.1 in ×ばつ 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, along with reconstructions and replicas, to demonstrate how it may have looked and worked.

In 2005, a team from Cardiff University led by Mike Edmunds 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. These scans suggest that the mechanism 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... )

MATLAB (Matrix Laboratory) is a proprietary multi-paradigm programming language and numeric computing environment developed by MathWorks. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other languages.

Although MATLAB is intended primarily for numeric computing, an optional toolbox uses the MuPAD symbolic engine allowing access to symbolic computing abilities. An additional package, Simulink, adds graphical multi-domain simulation and model-based design for dynamic and embedded systems.
As of 2020^[update] , MATLAB has more than four million users worldwide. They come from various backgrounds of engineering, science, and economics. As of 2017^[update] , more than 5000 global colleges and universities use MATLAB to support instruction and research. (Full article... )

Scala (/ˈskɑːlɑː/ SKAH-lah) is a strongly statically typed high-level general-purpose programming language that supports both object-oriented programming and functional programming. Designed to be concise, many of Scala's design decisions are intended to address criticisms of Java.

Scala source code can be compiled to Java bytecode and run on a Java virtual machine (JVM). Scala can also be transpiled to JavaScript to run in a browser, or compiled directly to a native executable. When running on the JVM, Scala provides language interoperability with Java so that libraries written in either language may be referenced directly in Scala or Java code. Like Java, Scala is object-oriented, and uses a syntax termed curly-brace which is similar to the language C. Since Scala 3, there is also an option to use the off-side rule (indenting) to structure blocks, and its use is advised. Martin Odersky has said that this turned out to be the most productive change introduced in Scala 3.

Unlike Java, Scala has many features of functional programming languages (like Scheme, Standard ML, and Haskell), including currying, immutability, lazy evaluation, and pattern matching. It also has an advanced type system supporting algebraic data types, covariance and contravariance, higher-order types (but not higher-rank types), anonymous types, operator overloading, optional parameters, named parameters, raw strings, and an experimental exception-only version of algebraic effects that can be seen as a more powerful version of Java's checked exceptions. (Full article... )

Information privacy is the relationship between the collection and dissemination of data, technology, the public expectation of privacy, contextual information norms, and the legal and political issues surrounding them. It is also known as data privacy or data protection. (Full article... )

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 fulfill 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 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 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... )

COBOL (Common Business-Oriented Language; /ˈkoʊbɒl,-bɔːl/ ) is a compiled English-like computer programming language designed for business use. It is an imperative, procedural, and, since 2002, object-oriented language. COBOL is primarily used in business, finance, and administrative systems for companies and governments. COBOL is still widely used in applications deployed on mainframe computers, such as large-scale batch and transaction processing jobs. Many large financial institutions were developing new systems in the language as late as 2006, but most programming in COBOL today is purely to maintain existing applications. Programs are being moved to new platforms, rewritten in modern languages, or replaced with other software.

COBOL's design was started in 1959 by CODASYL and was partly based on the programming language FLOW-MATIC, designed by Grace Hopper. It was created as part of a U.S. Department of Defense effort to create a portable programming language for data processing. It was originally seen as a stopgap, but the Defense Department promptly pressured computer manufacturers to provide it, resulting in its widespread adoption. It was standardized in 1968 and has been revised five times. Expansions include support for structured and object-oriented programming. The current standard is ISO/IEC 1989:2023.

COBOL statements have prose syntax such as MOVExTOy, which was designed to be self-documenting and highly readable. However, it is verbose and uses over 300 reserved words compared to the succinct and mathematically inspired syntax of other languages. (Full article... )