The history of computer science began long before the modern discipline of computer science that emerged in the twentieth century. The progression, from mechanical inventions and mathematical theories towards the modern concepts and machines, formed a major academic field and the basis of a massive world-wide industry. Computer science, or computing science, is the study of the theoretical foundations of information and computation and their implementation and application in computer systems. ...

The history of computing is longer than the history of computing hardware and modern computing technology and includes the history of methods intended for pen and paper or for chalk and slate, with or without the aid of tables. ... Computing hardware has been an important component of the process of calculation and data storage since it became useful for numerical values to be processed and shared. ... The history of computing hardware starting in the 1960s begins with the development of the integrated circuit (IC), which formed the basis of the first computer kits and home computers in the 1970s, notable examples being the MITS Altair, Apple II and Commodore PET; and which eventually powered personal and... The history of computing hardware in former Soviet Bloc is somewhat different from that of Western countries. ... The history of computer operating systems recapitulates to a degree, the recent history of computing. ... This article does not cite any references or sources. ... It has been suggested that the section History from the article Programming language be merged into this article or section. ... Artificial Intelligence was founded in the early 1950s by an eclectic group of visionaries who claimed to be on the verge of changing the world and mans place in it. ... The graphical user interface, or GUI (IPA: ), is a computer interface that uses graphic icons and controls in addition to text. ... Today, the Web and the Internet allow connectivity from literally everywhere on earth—even ships at sea and in outer space. ... Home video-game systems became popular during the 1970s and 80s. ... This article presents a detailed timeline of events in the history of computing. ... This article presents a timeline of events in the history of computing from Prehistory until 1949. ... This article presents a detailed timeline of events in the history of computing from 1950 to 1979. ... This article presents a timeline of events in the history of computing from 1980 to 1989. ... This article presents a detailed timeline of events in the history of computing from 1990 to the present. ...

Early history

Early computation

Main article: History of computing

The earliest known tool for use in computation was the abacus, and it was thought to have been invented in Babylon circa 2400 BCE. Its original style of usage was by lines drawn in sand with pebbles. Abaci, of a more modern design, are still used as calculation tools today. The history of computing is longer than the history of computing hardware and modern computing technology and includes the history of methods intended for pen and paper or for chalk and slate, with or without the aid of tables. ... It has been suggested that Abax be merged into this article or section. ... For other uses, see Babylon (disambiguation). ... (Redirected from 2400 BCE) (25th century BC - 24th century BC - 23rd century BC - other centuries) (4th millennium BC - 3rd millennium BC - 2nd millennium BC) Events 2900 - 2334 BC -- Mesopotamian wars of the Early Dynastic period 2350 BC - End of the Early Dynastic IIIb Period in Mesopotamia 2334 - 2279 BC -- Sargon...

In 1115 BCE, the South Pointing Chariot was invented in ancient China. It was the first known geared mechanism to use a differential gear, which was later used in analog computers. The Chinese also invented a more sophisticated abacus from around the 2nd century BCE known as the Chinese abacus). (Redirected from 1115 BCE) Centuries: 13th century BC - 12th century BC - 11th century BC Decades: 1160s BC 1150s BC 1140s BC 1130s BC 1120s BC - 1110s BC - 1100s BC 1090s BC 1080s BC 1070s BC 1060s BC Events and Trends 1115 BC - Zhou cheng wang becomes king of the Zhou... South Pointing Chariot (replica) Supposedly invented sometime around 2600BC in China by the Yellow Emperor Huang Di, the South Pointing Chariot (Zhi Nan Ju 指南車) is widely regarded as the most complex geared mechanism of the ancient Chinese civilization. ... China is the worlds oldest continuous major civilization, with written records dating back about 3,500 years and with 5,000 years being commonly used by Chinese as the age of their civilization. ... Spur gears found on a piece of farm equipment A gear is a wheel with teeth around its circumference, the purpose of the teeth being to mesh with similar teeth on another mechanical device -- possibly another gear wheel -- so that force can be transmitted between the two devices in a... In this differential, input torque is applied to the ring gear (blue). ... A page from the Bombardiers Information File (BIF) that describes the components and controls of the Norden bombsight. ... (3rd century BC - 2nd century BC - 1st century BC - other centuries) (2nd millennium BC - 1st millennium BC - 1st millennium AD) Events BC 168 Battle of Pydna -- Macedonian phalanx defeated by Romans BC 148 Rome conquers Macedonia BC 146 Rome destroys Carthage in the Third Punic War BC 146 Rome conquers... Chinese abacus or suanpan The suanpan (Simplified Chinese: 算盘; Traditional Chinese: 算盤; Pinyin: suànpán) of the Chinese dates from the Han Dynasty (202 BCE - 184 CE). ...

In the 5th century BCE in ancient India, the grammarian Pāṇini formulated the grammar of Sanskrit in 3959 rules known as the Ashtadhyayi which was highly systematized and technical. Panini used metarules, transformations and recursions with such sophistication that his grammar had the computing power equivalent to a Turing machine. (6th century BC - 5th century BC - 4th century BC - other centuries) (2nd millennium BC - 1st millennium BC - 1st millennium AD) Events Demotic becomes the dominant script of ancient Egypt Persians invade Greece twice (Persian Wars) Battle of Marathon (490) Battle of Salamis (480) Athenian empire formed and falls Peloponnesian War... The History of India begins with the Indus Valley Civilization, which flourished in the north-western part of the Indian subcontinent from 3300 to 1700 BC. This Bronze Age civilization was followed by the Iron Age Vedic period, which witnessed the rise of major kingdoms known as the Mahajanapadas. ... This article is about grammar from a linguistic perspective. ... Indian postage stamp depicting (2004), with the implication that he used (पाणिनि; IPA ) was an ancient Indian grammarian from Gandhara (traditionally 520–460 BC, but estimates range from the 7th to 4th centuries BC). ... For the rules of English grammar, see English grammar and Disputes in English grammar. ... The Sanskrit language ( , for short ) is a classical language of India, a liturgical language of Hinduism, Buddhism, Sikhism, and Jainism, and one of the 23 official languages of India. ... The Ashtadhyayi (Ạṣtādhyāyī, meaning eight chapters) is the earliest known grammar of Sanskrit, and one of the first works on descriptive linguistics, generative linguistics, or linguistics altogether. ... Look up transformation in Wiktionary, the free dictionary. ... A visual form of recursion known as the Droste effect. ... RAM (Random Access Memory) Look up computing in Wiktionary, the free dictionary. ... An artistic representation of a Turing Machine . ...

Between 200 BCE and 400 CE, Jaina mathematicians in India invented the logarithm. From the 13th century, logarithmic tables were produced by Muslim mathematicians. (Redirected from 200 BCE) Centuries: 3rd century BC - 2nd century BC - 1st century BC Decades: 250s BC 240s BC 230s BC 220s BC 210s BC - 200s BC - 190s BC 180s BC 170s BC 160s BC 150s BC Years: 205 BC 204 BC 203 BC 202 BC 201 BC - 200 BC... Events First invasion of Italy by Alaric (probable date). ... This article is under construction. ... Logarithms to various bases: is to base e, is to base 10, and is to base 1. ... (12th century - 13th century - 14th century - other centuries) As a means of recording the passage of time, the 13th century was that century which lasted from 1201 to 1300. ... Islamic mathematics is the profession of Muslim Mathematicians. ...

When John Napier discovered logarithms for computational purposes in the early 16th century, there followed a period of considerable progress by inventors and scientists in making calculating tools. For other people with the same name, see John Napier (disambiguation). ... (15th century - 16th century - 17th century - more centuries) As a means of recording the passage of time, the 16th century was that century which lasted from 1501 to 1600. ...

None of the early computational devices were really computers in the modern sense, and it took considerable advancement in mathematics and theory before the first modern computers could be designed. This article is about the machine. ...

Algorithms

In the 7th century, Indian mathematician Brahmagupta gave the first explanation of the Hindu-Arabic numeral system and the use of zero as both a placeholder and a decimal digit. The 7th century is the period from 601 - 700 in accordance with the Julian calendar in the Christian Era. ... This article is under construction. ... Brahmagupta (ब्रह्मगुप्त) ( ) (589–668) was an Indian mathematician and astronomer. ... I like cream cheese, it tastes good on toast. ... For other senses of this word, see zero or 0. ... For the World of Warcraft ex-NPC, see Captain Placeholder. ... In mathematics and computer science, a numerical digit is a symbol, e. ...

Approximately around the year 825, Persian mathematician Al-Khwarizmi wrote a book, On the Calculation with Hindu Numerals, that was principally responsible for the diffusion of the Indian system of numeration in the Middle East and then Europe. Around the 12th century, there was translation of this book written into Latin: Algoritmi de numero Indorum. These books presented newer concepts to perform a series of steps in order to accomplish a task such as the systematic application of arithmetic to algebra. By derivation from his name, we have the term algorithm. Events Egbert of Wessex defeats Beornwulf of Mercia at Ellandun. ... Soviet postage stamp commemorating the 1200th anniversary of Muhammad al‑Khwarizmi in 1983. ... I like cream cheese, it tastes good on toast. ... A map showing countries commonly considered to be part of the Middle East The Middle East is a region comprising the lands around the southern and eastern parts of the Mediterranean Sea, a territory that extends from the eastern Mediterranean Sea to the Persian Gulf. ... For other uses, see Europe (disambiguation). ... (11th century - 12th century - 13th century - other centuries) As a means of recording the passage of time, the 12th century was that century which lasted from 1101 to 1200. ... For other uses, see Latin (disambiguation). ... In mathematics, computing, linguistics, and related disciplines, an algorithm is a finite list of well-defined instructions for accomplishing some task that, given an initial state, will terminate in a defined end-state. ...

Binary logic

Around the 3rd century BC, Indian mathematician Pingala invented the binary numeral system. In this system, still used today to process all modern computers, a sequence of ones and zeros can represent any number. The 3rd century BC started the first day of 300 BC and ended the last day of 201 BC. It is considered part of the Classical era, epoch, or historical period. ... Pingala (पिङ्गल ) is the supposed author of the Chandas shastra (, also Chandas sutra ), a Sanskrit treatise on prosody considered one of the Vedanga. ... The binary numeral system, or base-2 number system, is a numeral system that represents numeric values using two symbols, usually 0 and 1. ... This article is about the number one. ...

In 1703, Gottfried Leibniz developed logic in a formal, mathematical sense with his writings on the binary numeral system. In his system, the ones and zeros also represent true and false values or on and off states. But it took more than a century before George Boole published his Boolean algebra in 1854 with a complete system that allowed computational processes to be mathematically modeled. Events February 2 - Earthquake in Aquila, Italy February 4 - In Japan, the 47 samurai commit seppuku (ritual suicide) February 14 - Earthquake in Norcia, Italy April 21 - Company of Quenching of Fire (ie. ... “Leibniz” redirects here. ... Logic (from Classical Greek λόγος logos; meaning word, thought, idea, argument, account, reason, or principle) is the study of the principles and criteria of valid inference and demonstration. ... George Boole [], (November 2, 1815 – December 8, 1864) was a British mathematician and philosopher. ... Boolean algebra is the finitary algebra of two values. ... 1854 (MDCCCLIV) was a common year starting on Sunday (see link for calendar). ...

By this time, the first mechanical devices driven by a binary pattern had been invented. The industrial revolution had driven forward the mechanization of many tasks, and this included weaving. Punch cards controlled Joseph Marie Jacquard's loom in 1801, where a hole punched in the card indicated a binary one and an unpunched spot indicated a binary zero. Jacquard's loom was far from being a computer, but it did illustrate that machines could be driven by binary systems. A Watt steam engine, the steam engine that propelled the Industrial Revolution in Britain and the world. ... Tweed loom, Harris, 2004 Woven sheet Weaving is an ancient textile art and craft that involves placing two sets of threads or yarn called the warp and weft of the loom and turning them into cloth. ... The punch card (or Hollerith card) is a recording medium for holding information for use by automated data processing machines. ... This does not adequately cite its references or sources. ... The Union Jack, flag of the newly formed United Kingdom of Great Britain and Ireland. ...

The Analytical Engine

It wasn't until Charles Babbage, considered the "father of computing," that the modern computer began to take shape with his work on the Analytical Engine. The device, though never successfully built, had all of the functionality in its design of a modern computer. He first described it in 1837 -- more than 100 years before any similar device was successfully constructed. The difference between Babbage's Engine and preceding devices is simple - he designed his to be programmed. Babbage redirects here. ... The analytical engine, an important step in the history of computers, was the design of a mechanical general-purpose computer by the British professor of mathematics Charles Babbage. ... Queen Victoria, Queen of the United Kingdom (1837 - 1901) 1837 (MDCCCXXXVII) was a common year starting on Sunday (see link for calendar). ...

During their collaboration, mathematician Ada Lovelace published the first ever computer programs in a comprehensive set of notes on the analytical engine. Because of this, Lovelace is popularly considered the first computer programmer, but some scholars contend that the programs published under her name were originally created by Babbage. Ada Lovelace Augusta Ada King, Countess of Lovelace (December 10, 1815 – November 27, 1852), born Augusta Ada Byron, is mainly known for having written a description of Charles Babbages early mechanical general-purpose computer, the analytical engine. ... A computer program (often simply called a program) is an example of computer software that prescribes the actions (computations) that are to be carried out by a computer. ... In 1840 Charles Babbage was invited to give a seminar at the University of Turin about his analytical engine. ... In computing, a programmer is someone who does computer programming and develops computer software. ...

Birth of computer science

Before the 1920s, computers were human clerks that performed computations. They were usually under the lead of a physicist. Many thousands of computers were employed in commerce, government, and research establishments. Most of these computers were women, and they were known to have a degree in calculus. Some performed astronomical calculations for calendars.

After the 1920s, the expression computing machine referred to any machine that performed the work of a human computer, especially those in accordance with effective methods of the Church-Turing thesis. The thesis states that a mathematical method is effective if it could be set out as a list of instructions able to be followed by a human clerk with paper and pencil, for as long as necessary, and without ingenuity or insight. In computability theory the Church-Turing thesis, Churchs thesis, Churchs conjecture or Turings thesis, named after Alonzo Church and Alan Turing, is a hypothesis about the nature of mechanical calculation devices, such as electronic computers. ...

Machines that computed with continuous values became known as the analog kind. They used machinery that represented continuous numeric quantities, like the angle of a shaft rotation or difference in electrical potential.

Digital machinery, in contrast to analog, were able to render a state of a numeric value and store each individual digit. Digital machinery used difference engines or relays before the invention of faster memory devices.

The phrase computing machine gradually gave away, after the late 1940s, to just computer as the onset of electronic digital machinery became common. These computers were able to perform the calculations that were performed by the previous human clerks.

Since the values stored by digital machines were not bound to physical properties like analog devices, a logical computer, based on digital equipment, was able to do anything that could be described "purely mechanical." Alan Turing, known as the Father of Computer Science, invented such a logical computer known as the Turing Machine, which later evolved into the modern computer. These new computers were also able to perform non-numeric computations, like music. Alan Mathison Turing, OBE, FRS (23 June 1912 – 7 June 1954) was an English mathematician, logician, and cryptographer. ... An artistic representation of a Turing Machine . ...

From the time when computational processes were performed by human clerks, the study of computability began a science by being able to make evident which was not explicit into ordinary sense more immediate.

Emergence of a discipline

The theoretical groundwork

The mathematical foundations of modern computer science began to be laid by Kurt Gödel with his incompleteness theorem (1931). In this theorem, he showed that there were limits to what could be proved and disproved within a formal system. This led to work by Gödel and others to define and describe these formal systems, including concepts such as mu-recursive functions and lambda-definable functions. Kurt Gödel (IPA: ) (April 28, 1906 Brünn, Austria-Hungary (now Brno, Czech Republic) – January 14, 1978 Princeton, New Jersey) was an Austrian American mathematician and philosopher. ... In mathematical logic, Gödels incompleteness theorems are two celebrated theorems proven by Kurt Gödel in 1931. ... Year 1931 (MCMXXXI) was a common year starting on Thursday (link will display full 1931 calendar) of the Gregorian calendar. ... In mathematical logic and computer science, the recursive functions are a class of functions from natural numbers to natural numbers which are computable in some intuitive sense. ... The lambda calculus is a formal system designed to investigate function definition, function application, and recursion. ...

1936 was a key year for computer science. Alan Turing and Alonzo Church independently, and also together, introduced the formalization of an algorithm, with limits on what can be computed, and a "purely mechanical" model for computing. 1936 (MCMXXXVI) was a leap year starting on Wednesday (link will take you to calendar). ... ‹ The template below (Expand) is being considered for deletion. ... In mathematics, computing, linguistics, and related disciplines, an algorithm is a finite list of well-defined instructions for accomplishing some task that, given an initial state, will terminate in a defined end-state. ...

These topics are covered by what is now called the Church–Turing thesis, a hypothesis about the nature of mechanical calculation devices, such as electronic computers. The thesis claims that any calculation that is possible can be performed by an algorithm running on a computer, provided that sufficient time and storage space are available. In computability theory the Church–Turing thesis (also known as Churchs thesis, Churchs conjecture and Turings thesis) is a hypothesis about the nature of mathematical functions that can be computed by a digital computer or a human with a pencil and paper following a set of rules. ...

Turing also included with the thesis a description of the Turing machine. A Turing machine has an infinitely long tape and a read/write head that can move along the tape, changing the values along the way. Clearly such a machine could never be built, but nonetheless, the model can simulate the computation of any algorithm which can be performed on a modern computer. An artistic representation of a Turing Machine . ...

Turing is so important to computer science that his name is also featured on the Turing Award and the Turing test. He contributed greatly to British code-breaking successes in the Second World War, and continued to design computers and software through the 1940s, but committed suicide in 1954. The A.M. Turing Award is given annually by the Association for Computing Machinery to a person selected for contributions of a technical nature made to the computing community. ... For the Doctor Who novel named after the test, see The Turing Test (novel). ... Mushroom cloud from the nuclear explosion over Nagasaki rising 18 km into the air. ... This article does not cite any references or sources. ... Year 1954 (MCMLIV) was a common year (link will display full calendar) of the Gregorian calendar. ...

At a symposium on large-scale digital machinery in Cambridge, Turing said, "We are trying to build a machine to do all kinds of different things simply by programming rather than by the addition of extra apparatus".

In 1948, the first practical computer that could run stored programs, based on the Turing machine model, had been built - the Manchester Baby. Replica of the SSEM The Manchester Small-Scale Experimental Machine (SSEM), nicknamed Baby, was the first stored-program computer to run a program, on June 21, 1948. ...

In 1950, Britain's National Physical Laboratory completed Pilot ACE, a small scale programmable computer, based on Turing's philosophy. The National Physical Laboratory (NPL) is the national measurement standards laboratory for the United Kingdom, based at Bushy Park in Teddington in the London Borough of Richmond upon Thames. ... The Pilot ACE was one of the first computers built in the United Kingdom, at the National Physical Laboratory (NPL) in the late 1940s. ...

Shannon and information theory

Up to and during the 1930s, electrical engineers were able to build electronic circuits to solve mathematical and logic problems, but most did so in an ad hoc manner, lacking any theoretical rigor. This changed with Claude E. Shannon's publication of his 1937 master's thesis, A Symbolic Analysis of Relay and Switching Circuits. While taking an undergraduate philosophy class, Shannon had been exposed to Boole's work, and recognized that it could be used to arrange electromechanical relays (then used in telephone routing switches) to solve logic problems. This concept, of utilizing the properties of electrical switches to do logic, is the basic concept that underlies all electronic digital computers, and his thesis became the foundation of practical digital circuit design when it became widely known among the electrical engineering community during and after World War II. Claude Elwood Shannon (April 30, 1916 - February 24, 2001) has been called the father of information theory, and was the founder of practical digital circuit design theory. ... In his 1937 MIT masters thesis, A Symbolic Analysis of Relay and Switching Circuits, Claude Elwood Shannon proved that Boolean algebra and binary arithmetic could be used to simplify the arrangement of the electromechanical relays then used in telephone routing switches, then turned the concept upside down and also... George Boole [], (November 2, 1815 – December 8, 1864) was a British mathematician and philosopher. ...

Shannon went on to found the field of information theory with his 1948 paper entitled A Mathematical Theory of Communication, which applied probability theory to the problem of how to best encode the information a sender wants to transmit. This work is one of the theoretical foundations for many areas of study, including data compression and cryptography. Not to be confused with information technology, information science, or informatics. ... A Mathematical Theory of Communication, published in 1948 by mathematician and computer scientist Claude Shannon, was one of the founding works of the field of information theory. ... Probability theory is the branch of mathematics concerned with analysis of random phenomena. ... “Source coding” redirects here. ... The German Lorenz cipher machine, used in World War II for encryption of very high-level general staff messages Cryptography (or cryptology; derived from Greek κρυπτός kryptós hidden, and the verb γράφω gráfo write or λεγειν legein to speak) is the study of message secrecy. ...

Wiener and Cybernetics

From experiments with anti-aircraft systems that interpreted radar images to detect enemy planes, Norbert Wiener coined the term cybernetics from the Greek word for "steersman." He published "Cybernetics" in 1948, which influenced artificial intelligence. Wiener also compared computation, computing machinery, memory devices, and other cognitive similarities with his analysis of brain waves. This article or section is not written in the formal tone expected of an encyclopedia article. ... Cybernetics is the study of feedback and derived concepts such as communication and control in living organisms, machines and organisations. ... Garry Kasparov playing against Deep Blue, the first machine to win a chess game against a reigning world champion. ... Look up computation in Wiktionary, the free dictionary. ... The terms storage (U.K.) or memory (U.S.) refer to the parts of a digital computer that retain physical state (data) for some interval of time, possibly even after electrical power to the computer is turned off. ...

The first computer bug

Main article: Software bug

The first actual computer bug was a moth. It was stuck in between the relays on the Harvard Mark II.[1] While the invention of the term 'bug' is often but erroneously attributed to Grace Hopper, a rear admiral in the U.S. Navy, who supposedly logged the "bug" on September 9, 1945, most other accounts conflict at least with these details. According to these accounts, the actual date was September 9, 1947 when operators filed this 'incident' — along with the insect and the notation "First actual case of bug being found" (see software bug for details). A software bug is an error, flaw, mistake, failure, or fault in a computer program that prevents it from behaving as intended (e. ... A moth is an insect closely related to the butterfly. ... Rear Admiral Grace Murray Hopper (December 9, 1906 – January 1, 1992) was an American computer scientist and United States Navy officer. ... is the 252nd day of the year (253rd in leap years) in the Gregorian calendar. ... Year 1945 (MCMXLV) was a common year starting on Monday (link will display the full calendar). ... is the 252nd day of the year (253rd in leap years) in the Gregorian calendar. ... Year 1947 (MCMXLVII) was a common year starting on Wednesday (link will display full 1947 calendar) of the Gregorian calendar. ... A software bug is an error, flaw, mistake, failure, or fault in a computer program that prevents it from behaving as intended (e. ...

See also

• Computer science
• History of computing
• History of computing hardware
• Timeline of algorithms
• List of prominent pioneers in computer science
• List of computer term etymologies, the origins of computer science words

Computer science, or computing science, is the study of the theoretical foundations of information and computation and their implementation and application in computer systems. ... The history of computing is longer than the history of computing hardware and modern computing technology and includes the history of methods intended for pen and paper or for chalk and slate, with or without the aid of tables. ... Computing hardware has been an important component of the process of calculation and data storage since it became useful for numerical values to be processed and shared. ... The following timeline outlines the development of algorithms since their inception. ... Category: ... This is a list of the origins of computer-related terms (i. ...

References

• A Very Brief History of Computer Science
• Computer History Museum
• Computers: From the Past to the Present
• The First "Computer Bug" at the Online Library of the Naval Historical Center, retrieved February 28, 2006
• Bitsavers, an effort to capture, salvage, and archive historical computer software and manuals from minicomputers and mainframes of the 50s, 60s, 70s, and 80s