An operating system is system software that manages computer hardware and software resources and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is executed directly by the hardware and makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers; the dominant desktop operating system is Microsoft Windows with a market share of around 82.74%. MacOS by Apple Inc. is in second place, the varieties of Linux are collectively in third place. In the mobile sector, use in 2017 is up to 70% of Google's Android and according to third quarter 2016 data, Android on smartphones is dominant with 87.5 percent and a growth rate 10.3 percent per year, followed by Apple's iOS with 12.1 percent and a per year decrease in market share of 5.2 percent, while other operating systems amount to just 0.3 percent.
Linux distributions are dominant in supercomputing sectors. Other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications. A single-tasking system can only run one program at a time, while a multi-tasking operating system allows more than one program to be running in concurrency; this is achieved by time-sharing, where the available processor time is divided between multiple processes. These processes are each interrupted in time slices by a task-scheduling subsystem of the operating system. Multi-tasking may be characterized in co-operative types. In preemptive multitasking, the operating system slices the CPU time and dedicates a slot to each of the programs. Unix-like operating systems, such as Solaris and Linux—as well as non-Unix-like, such as AmigaOS—support preemptive multitasking. Cooperative multitasking is achieved by relying on each process to provide time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking.
32-bit versions of both Windows NT and Win9x, used preemptive multi-tasking. Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem. A multi-user operating system extends the basic concept of multi-tasking with facilities that identify processes and resources, such as disk space, belonging to multiple users, the system permits multiple users to interact with the system at the same time. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources to multiple users. A distributed operating system manages a group of distinct computers and makes them appear to be a single computer; the development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine; when computers in a group work in cooperation, they form a distributed system.
In an OS, distributed and cloud computing context, templating refers to creating a single virtual machine image as a guest operating system saving it as a tool for multiple running virtual machines. The technique is used both in virtualization and cloud computing management, is common in large server warehouses. Embedded operating systems are designed to be used in embedded computer systems, they are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources, they are compact and efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems. A real-time operating system is an operating system that guarantees to process events or data by a specific moment in time. A real-time operating system may be single- or multi-tasking, but when multitasking, it uses specialized scheduling algorithms so that a deterministic nature of behavior is achieved. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.
A library operating system is one in which the services that a typical operating system provides, such as networking, are provided in the form of libraries and composed with the application and configuration code to construct a unikernel: a specialized, single address space, machine image that can be deployed to cloud or embedded environments. Early computers were built to perform a series of single tasks, like a calculator. Basic operating system features were developed in the 1950s, such as resident monitor functions that could automatically run different programs in succession to speed up processing. Operating systems did not exist in their more complex forms until the early 1960s. Hardware features were added, that enabled use of runtime libraries and parallel processing; when personal computers became popular in the 1980s, operating systems were made for them similar in concept to those used on larger computers. In the 1940s, the earliest electronic digital systems had no operating systems.
Electronic systems of this time were programmed on rows of mechanical switches or by jumper wires on plug boards. These were special-purpose systems that, for example, generated ballistics tables for the military or controlled the pri
The Solar System is the gravitationally bound planetary system of the Sun and the objects that orbit it, either directly or indirectly. Of the objects that orbit the Sun directly, the largest are the eight planets, with the remainder being smaller objects, such as the five dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly—the moons—two are larger than the smallest planet, Mercury; the Solar System formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The vast majority of the system's mass is in the Sun, with the majority of the remaining mass contained in Jupiter; the four smaller inner planets, Venus and Mars, are terrestrial planets, being composed of rock and metal. The four outer planets are giant planets, being more massive than the terrestrials; the two largest and Saturn, are gas giants, being composed of hydrogen and helium. All eight planets have circular orbits that lie within a nearly flat disc called the ecliptic.
The Solar System contains smaller objects. The asteroid belt, which lies between the orbits of Mars and Jupiter contains objects composed, like the terrestrial planets, of rock and metal. Beyond Neptune's orbit lie the Kuiper belt and scattered disc, which are populations of trans-Neptunian objects composed of ices, beyond them a newly discovered population of sednoids. Within these populations are several dozen to tens of thousands of objects large enough that they have been rounded by their own gravity; such objects are categorized as dwarf planets. Identified dwarf planets include the trans-Neptunian objects Pluto and Eris. In addition to these two regions, various other small-body populations, including comets and interplanetary dust clouds travel between regions. Six of the planets, at least four of the dwarf planets, many of the smaller bodies are orbited by natural satellites termed "moons" after the Moon; each of the outer planets is encircled by planetary rings of dust and other small objects.
The solar wind, a stream of charged particles flowing outwards from the Sun, creates a bubble-like region in the interstellar medium known as the heliosphere. The heliopause is the point at which pressure from the solar wind is equal to the opposing pressure of the interstellar medium; the Oort cloud, thought to be the source for long-period comets, may exist at a distance a thousand times further than the heliosphere. The Solar System is located in the Orion Arm, 26,000 light-years from the center of the Milky Way galaxy. For most of history, humanity did not understand the concept of the Solar System. Most people up to the Late Middle Ages–Renaissance believed Earth to be stationary at the centre of the universe and categorically different from the divine or ethereal objects that moved through the sky. Although the Greek philosopher Aristarchus of Samos had speculated on a heliocentric reordering of the cosmos, Nicolaus Copernicus was the first to develop a mathematically predictive heliocentric system.
In the 17th century, Galileo discovered that the Sun was marked with sunspots, that Jupiter had four satellites in orbit around it. Christiaan Huygens followed on from Galileo's discoveries by discovering Saturn's moon Titan and the shape of the rings of Saturn. Edmond Halley realised in 1705 that repeated sightings of a comet were recording the same object, returning once every 75–76 years; this was the first evidence that anything other than the planets orbited the Sun. Around this time, the term "Solar System" first appeared in English. In 1838, Friedrich Bessel measured a stellar parallax, an apparent shift in the position of a star created by Earth's motion around the Sun, providing the first direct, experimental proof of heliocentrism. Improvements in observational astronomy and the use of unmanned spacecraft have since enabled the detailed investigation of other bodies orbiting the Sun; the principal component of the Solar System is the Sun, a G2 main-sequence star that contains 99.86% of the system's known mass and dominates it gravitationally.
The Sun's four largest orbiting bodies, the giant planets, account for 99% of the remaining mass, with Jupiter and Saturn together comprising more than 90%. The remaining objects of the Solar System together comprise less than 0.002% of the Solar System's total mass. Most large objects in orbit around the Sun lie near the plane of Earth's orbit, known as the ecliptic; the planets are close to the ecliptic, whereas comets and Kuiper belt objects are at greater angles to it. All the planets, most other objects, orbit the Sun in the same direction that the Sun is rotating. There are exceptions, such as Halley's Comet; the overall structure of the charted regions of the Solar System consists of the Sun, four small inner planets surrounded by a belt of rocky asteroids, four giant planets surrounded by the Kuiper belt of icy objects. Astronomers sometimes informally divide this structure into separate regions; the inner Solar System includes the asteroid belt. The outer Solar System is including the four giant planets.
Since the discovery of the Kuiper belt, the outermost parts of the Solar Sys
Fortran is a general-purpose, compiled imperative programming language, suited to numeric computation and scientific computing. Developed by IBM in the 1950s for scientific and engineering applications, FORTRAN came to dominate this area of programming early on and has been in continuous use for over half a century in computationally intensive areas such as numerical weather prediction, finite element analysis, computational fluid dynamics, computational physics and computational chemistry, it is a popular language for high-performance computing and is used for programs that benchmark and rank the world's fastest supercomputers. Fortran encompasses a lineage of versions, each of which evolved to add extensions to the language while retaining compatibility with prior versions. Successive versions have added support for structured programming and processing of character-based data, array programming, modular programming and generic programming, high performance Fortran, object-oriented programming and concurrent programming.
Fortran's design was the basis for many other programming languages. Among the better known is BASIC, based on FORTRAN II with a number of syntax cleanups, notably better logical structures, other changes to more work in an interactive environment; the names of earlier versions of the language through FORTRAN 77 were conventionally spelled in all-capitals. The capitalization has been dropped in referring to newer versions beginning with Fortran 90; the official language standards now refer to the language as "Fortran" rather than all-caps "FORTRAN". In late 1953, John W. Backus submitted a proposal to his superiors at IBM to develop a more practical alternative to assembly language for programming their IBM 704 mainframe computer. Backus' historic FORTRAN team consisted of programmers Richard Goldberg, Sheldon F. Best, Harlan Herrick, Peter Sheridan, Roy Nutt, Robert Nelson, Irving Ziller, Lois Haibt, David Sayre, its concepts included easier entry of equations into a computer, an idea developed by J. Halcombe Laning and demonstrated in the Laning and Zierler system of 1952.
A draft specification for The IBM Mathematical Formula Translating System was completed by November 1954. The first manual for FORTRAN appeared in October 1956, with the first FORTRAN compiler delivered in April 1957; this was the first optimizing compiler, because customers were reluctant to use a high-level programming language unless its compiler could generate code with performance comparable to that of hand-coded assembly language. While the community was skeptical that this new method could outperform hand-coding, it reduced the number of programming statements necessary to operate a machine by a factor of 20, gained acceptance. John Backus said during a 1979 interview with Think, the IBM employee magazine, "Much of my work has come from being lazy. I didn't like writing programs, so, when I was working on the IBM 701, writing programs for computing missile trajectories, I started work on a programming system to make it easier to write programs."The language was adopted by scientists for writing numerically intensive programs, which encouraged compiler writers to produce compilers that could generate faster and more efficient code.
The inclusion of a complex number data type in the language made Fortran suited to technical applications such as electrical engineering. By 1960, versions of FORTRAN were available for the IBM 709, 650, 1620, 7090 computers; the increasing popularity of FORTRAN spurred competing computer manufacturers to provide FORTRAN compilers for their machines, so that by 1963 over 40 FORTRAN compilers existed. For these reasons, FORTRAN is considered to be the first used programming language supported across a variety of computer architectures; the development of Fortran paralleled the early evolution of compiler technology, many advances in the theory and design of compilers were motivated by the need to generate efficient code for Fortran programs. The initial release of FORTRAN for the IBM 704 contained 32 statements, including: DIMENSION and EQUIVALENCE statements Assignment statements Three-way arithmetic IF statement, which passed control to one of three locations in the program depending on whether the result of the arithmetic statement was negative, zero, or positive IF statements for checking exceptions.
The arithmetic IF statement was reminiscent of a three-way comparison instruction available on the 704. The statement provided the only way to compare numbers – by testing their difference, with an attendant risk of overflow; this deficiency was overcome by "logical" facilities introduced in FORTRAN IV. The FREQUENCY statement was used to give branch probabilities for the three branch cases of the arithmetic IF statement; the first FORTRAN compiler used this weighting to perform at compile time a Monte Carlo simulation of the generated code, the results of which were used to optimize the
A computer terminal is an electronic or electromechanical hardware device, used for entering data into, displaying or printing data from, a computer or a computing system. The teletype was an example of an early day hardcopy terminal, predated the use of a computer screen by decades; the acronym CRT, which once referred to a computer terminal, has come to refer to a type of screen of a personal computer. Early terminals were inexpensive devices but slow compared to punched cards or paper tape for input, but as the technology improved and video displays were introduced, terminals pushed these older forms of interaction from the industry. A related development was timesharing systems, which evolved in parallel and made up for any inefficiencies of the user's typing ability with the ability to support multiple users on the same machine, each at their own terminal; the function of a terminal is confined to input of data. A terminal that depends on the host computer for its processing power is called a "dumb terminal" or a thin client.
A personal computer can run terminal emulator software that replicates the function of a terminal, sometimes allowing concurrent use of local programs and access to a distant terminal host system. The terminal of the first working programmable automatic digital Turing-complete computer, the Z3, had a keyboard and a row of lamps to show results. Early user terminals connected to computers were electromechanical teleprinters/teletypewriters, such as the Teletype Model 33 ASR used for telegraphy or the Friden Flexowriter. Keyboard/printer terminals that came included the IBM 2741 and the DECwriter LA30. Respective top speeds of teletypes, IBM 2741 and LA30 were 15 and 30 characters per second. Although at that time "paper was king" the speed of interaction was limited. Early video computer displays were sometimes nicknamed "Glass TTYs" or "Visual Display Units", used no CPU, instead relying on individual logic gates or primitive LSI chips, they became popular Input-Output devices on many different types of computer system once several suppliers gravitated to a set of common standards: ASCII character set, but early/economy models supported only capital letters RS-232 serial ports 24 lines of 80 characters of text.
Models sometimes had two character-width settings. Some type of cursor that can be positioned. Implementation of at least 3 control codes: Carriage Return, Line-Feed, Bell, but many more, such as Escape sequences to provide underlining, dim or reverse-video character highlighting, to clear the display and position the cursor; the Datapoint 3300 from Computer Terminal Corporation was announced in 1967 and shipped in 1969, making it one of the earliest stand-alone display-based terminals. It solved the memory space issue mentioned above by using a digital shift-register design, using only 72 columns rather than the more common choice of 80. Starting with the Datapoint 3300, by the late 1970s and early 1980s, there were dozens of manufacturers of terminals, including Lear-Siegler, ADDS, Data General, DEC, Hazeltine Corporation, Heath/Zenith, Hewlett Packard, IBM, Volker-Craig, Wyse, many of which had incompatible command sequences; the great variations in the control codes between makers gave rise to software that identified and grouped terminal types so the system software would display input forms using the appropriate control codes.
The great majority of terminals were monochrome, manufacturers variously offering green, white or amber and sometimes blue screen phosphors.. Terminals with modest color capability were available but not used. An "intelligent" terminal does its own processing implying a microprocessor is built in, but not all terminals with microprocessors did any real processing of input: the main computer to which it was attached would have to respond to each keystroke; the term "intelligent" in this context dates from 1969. Notable examples include the IBM 2250 and IBM 2260, predecessors to the IBM 3270 and introduced with System/360 in 1964. Most terminals were connected to minicomputers or mainframe computers and had a green or amber screen. Terminals communicate wi
Kenneth Lane Thompson is an American pioneer of computer science. Having worked at Bell Labs for most of his career, Thompson designed and implemented the original Unix operating system, he invented the B programming language, the direct predecessor to the C programming language, was one of the creators and early developers of the Plan 9 operating systems. Since 2006, Thompson has worked at Google. Other notable contributions included his work on regular expressions and early computer text editors QED and ed, the definition of the UTF-8 encoding, his work on computer chess that included creation of endgame tablebases and the chess machine Belle. Thompson was born in New Orleans; when asked how he learned to program, Thompson stated, "I was always fascinated with logic and in grade school I'd work on arithmetic problems in binary, stuff like that. Just because I was fascinated." Thompson received a Bachelor of Science in 1965 and a Master's degree in 1966, both in Electrical Engineering and Computer Science, from the University of California, where his master's thesis advisor was Elwyn Berlekamp.
Thompson was hired by Bell Labs in 1966. In the 1960s at Bell Labs and Dennis Ritchie worked on the Multics operating system. While writing Multics, Thompson created the Bon programming language, he created a video game called Space Travel. Bell Labs withdrew from the MULTICS project. In order to go on playing the game, Thompson found an old PDP-7 machine and rewrote Space Travel on it; the tools developed by Thompson became the Unix operating system: Working on a PDP-7, a team of Bell Labs researchers led by Thompson and Ritchie, including Rudd Canaday, developed a hierarchical file system, the concepts of computer processes and device files, a command-line interpreter, some small utility programs. In 1970, Brian Kernighan suggested the name "Unix", in a somewhat treacherous pun on the name "Multics". After initial work on Unix, Thompson decided that Unix needed a system programming language and created B, a precursor to Ritchie's C. In the 1960s, Thompson began work on regular expressions. Thompson had developed the CTSS version of the editor QED, which included regular expressions for searching text.
QED and Thompson's editor ed contributed to the eventual popularity of regular expressions, regular expressions became pervasive in Unix text processing programs. All programs that work with regular expressions today use some variant of Thompson's notation, he invented Thompson's construction algorithm used for converting regular expression into nondeterministic finite automaton in order to make expression matching faster. Throughout the 1970s, Thompson and Ritchie collaborated on the Unix operating system. In a 2011 interview, Thompson stated that the first versions of Unix were written by him, that Ritchie began to advocate for the system and helped to develop it: I did the first of two or three versions of UNIX all alone, and Dennis became an evangelist. There was a rewrite in a higher-level language that would come to be called C, he worked on the language and on the I/O system, I worked on all the rest of the operating system. That was for the PDP-11, serendipitous, because, the computer that took over the academic community.
Feedback from Thompson's Unix development was instrumental in the development of the C programming language. Thompson would say that the C language "grew up with one of the rewritings of the system and, as such, it became perfect for writing systems". In 1975, Thompson went to his alma mater, UC Berkeley. There, he helped to install Version 6 Unix on a PDP-11/70. Unix at Berkeley would become maintained as its own system, known as the Berkeley Software Distribution. Along with Joseph Condon, Thompson created the hardware and software for Belle, a world champion chess computer, he wrote programs for generating the complete enumeration of chess endings, known as endgame tablebases, for all 4, 5, 6-piece endings, allowing chess-playing computer programs to make "perfect" moves once a position stored in them is reached. With the help of chess endgame expert John Roycroft, Thompson distributed his first results on CD-ROM. Throughout the 1980s, Thompson and Ritchie continued revising Research Unix, which adopted a BSD codebase for the 8th, 9th, 10th editions.
In the mid-1980s, work began at Bell Labs on a new operating system as a replacement for Unix. Thompson was instrumental in the design and implementation of the Plan 9 from Bell Labs, a new operating system utilizing principles of Unix, but applying them more broadly to all major system facilities; some programs that were part of versions of Research Unix, such as mk and rc, were incorporated into Plan 9. Thompson tested early versions of the C++ programming language for Bjarne Stroustrup by writing programs in it, but refused to work in C++ due to frequent incompatibilities between versions. In a 2009 interview, Thompson expressed a negative view of C++, stating, "It does a lot of things half well and it's just a garbage heap of ideas that are mutually exclusive." In 1992, Thompson developed the UTF-8 encoding scheme together with Rob Pike. UTF-8 encoding has since become the dominant character encoding for the World Wide Web, accounting for more than half of all web pages. In the 1990s, work began on the Inferno operating system, another research operating system, based around a portable
Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars and light—are brought toward one another. On Earth, gravity gives weight to physical objects, the Moon's gravity causes the ocean tides; the gravitational attraction of the original gaseous matter present in the Universe caused it to begin coalescing, forming stars – and for the stars to group together into galaxies – so gravity is responsible for many of the large-scale structures in the Universe. Gravity has an infinite range, although its effects become weaker on farther objects. Gravity is most described by the general theory of relativity which describes gravity not as a force, but as a consequence of the curvature of spacetime caused by the uneven distribution of mass; the most extreme example of this curvature of spacetime is a black hole, from which nothing—not light—can escape once past the black hole's event horizon. However, for most applications, gravity is well approximated by Newton's law of universal gravitation, which describes gravity as a force which causes any two bodies to be attracted to each other, with the force proportional to the product of their masses and inversely proportional to the square of the distance between them.
Gravity is the weakest of the four fundamental forces of physics 1038 times weaker than the strong force, 1036 times weaker than the electromagnetic force and 1029 times weaker than the weak force. As a consequence, it has no significant influence at the level of subatomic particles. In contrast, it is the dominant force at the macroscopic scale, is the cause of the formation and trajectory of astronomical bodies. For example, gravity causes the Earth and the other planets to orbit the Sun, it causes the Moon to orbit the Earth, causes the formation of tides, the formation and evolution of the Solar System and galaxies; the earliest instance of gravity in the Universe in the form of quantum gravity, supergravity or a gravitational singularity, along with ordinary space and time, developed during the Planck epoch from a primeval state, such as a false vacuum, quantum vacuum or virtual particle, in a unknown manner. Attempts to develop a theory of gravity consistent with quantum mechanics, a quantum gravity theory, which would allow gravity to be united in a common mathematical framework with the other three forces of physics, are a current area of research.
Archimedes discovered the center of gravity of a triangle. He postulated that if the centers of gravity of two equal weights wasn't the same, it would be located in the middle of the line that joins them; the Roman architect and engineer Vitruvius in De Architectura postulated that gravity of an object didn't depend on weight but its "nature". Aryabhata first identified the force to explain why objects are not thrown out when the earth rotates. Brahmagupta described gravity as an attractive force and used the term "gruhtvaakarshan" for gravity. Modern work on gravitational theory began with the work of Galileo Galilei in the late 16th and early 17th centuries. In his famous experiment dropping balls from the Tower of Pisa, with careful measurements of balls rolling down inclines, Galileo showed that gravitational acceleration is the same for all objects; this was a major departure from Aristotle's belief that heavier objects have a higher gravitational acceleration. Galileo postulated air resistance as the reason that objects with less mass fall more in an atmosphere.
Galileo's work set the stage for the formulation of Newton's theory of gravity. In 1687, English mathematician Sir Isaac Newton published Principia, which hypothesizes the inverse-square law of universal gravitation. In his own words, "I deduced that the forces which keep the planets in their orbs must reciprocally as the squares of their distances from the centers about which they revolve: and thereby compared the force requisite to keep the Moon in her Orb with the force of gravity at the surface of the Earth; the equation is the following: F = G m 1 m 2 r 2 Where F is the force, m1 and m2 are the masses of the objects interacting, r is the distance between the centers of the masses and G is the gravitational constant. Newton's theory enjoyed its greatest success when it was used to predict the existence of Neptune based on motions of Uranus that could not be accounted for by the actions of the other planets. Calculations by both John Couch Adams and Urbain Le Verrier predicted the general position of the planet, Le Verrier's calculations are what led Johann Gottfried Galle to the discovery of Neptune.
A discrepancy in Mercury's orbit pointed out flaws in Newton's theory. By the end of the 19th century, it was known that its orbit showed slight perturbations that could not be accounted for under Newton's theory, but all searches for another perturbing body had been fruitless; the issue was resolved in 1915 by Albert Einstein's new theory of general relativity, which accounted for the small discrepancy in Mercury's orbit. This discrepancy was the advance in the perihelion of Mercury of 42.98 arcseconds per century. Although Newton's theory has been superseded by Einstein's general relativity, most modern non-relativistic gravitational calculations are still made using Newton
Nokia Bell Labs is an industrial research and scientific development company owned by Finnish company Nokia. Its headquarters are located in New Jersey. Other laboratories are located around the world. Bell Labs has its origins in the complex past of the Bell System. In the late 19th century, the laboratory began as the Western Electric Engineering Department and was located at 463 West Street in New York City. In 1925, after years of conducting research and development under Western Electric, the Engineering Department was reformed into Bell Telephone Laboratories and under the shared ownership of American Telephone & Telegraph Company and Western Electric. Researchers working at Bell Labs are credited with the development of radio astronomy, the transistor, the laser, the photovoltaic cell, the charge-coupled device, information theory, the Unix operating system, the programming languages C, C++, S. Nine Nobel Prizes have been awarded for work completed at Bell Laboratories. In 1880, when the French government awarded Alexander Graham Bell the Volta Prize of 50,000 francs (approximately US$10,000 at that time for the invention of the telephone, he used the award to fund the Volta Laboratory in Washington, D.
C. in collaboration with Sumner Tainter and Bell's cousin Chichester Bell. The laboratory was variously known as the Volta Bureau, the Bell Carriage House, the Bell Laboratory and the Volta Laboratory, it focused on the analysis and transmission of sound. Bell used his considerable profits from the laboratory for further research and education to permit the " diffusion of knowledge relating to the deaf": resulting in the founding of the Volta Bureau, located at Bell's father's house at 1527 35th Street N. W. in Washington, D. C, its carriage house became their headquarters in 1889. In 1893, Bell constructed a new building close by at 1537 35th Street N. W. to house the lab. This building was declared a National Historic Landmark in 1972. After the invention of the telephone, Bell maintained a distant role with the Bell System as a whole, but continued to pursue his own personal research interests; the Bell Patent Association was formed by Alexander Graham Bell, Thomas Sanders, Gardiner Hubbard when filing the first patents for the telephone in 1876.
Bell Telephone Company, the first telephone company, was formed a year later. It became a part of the American Bell Telephone Company. American Telephone & Telegraph Company and its own subsidiary company, took control of American Bell and the Bell System by 1889. American Bell held a controlling interest in Western Electric whereas AT&T was doing research into the service providers. In 1884, the American Bell Telephone Company created the Mechanical Department from the Electrical and Patent Department formed a year earlier. In 1896, Western Electric bought property at 463 West Street to station their manufacturers and engineers, supplying AT&T with their product; this included everything from telephones, telephone exchange switches, transmission equipment. In 1925, Bell Laboratories was developed to better consolidate the research activities of the Bell System. Ownership was evenly split between Western Electric and AT&T. Throughout the next decade the AT&T Research and Development branch moved into West Street.
Bell Labs carried out consulting work for the Bell Telephone Company, U. S. government work, a few workers were assigned to basic research. The first president of research at Bell Labs was Frank B. Jewett who stayed there until 1940. By the early 1940s, Bell Labs engineers and scientists had begun to move to other locations away from the congestion and environmental distractions of New York City, in 1967 Bell Laboratories headquarters was relocated to Murray Hill, New Jersey. Among the Bell Laboratories locations in New Jersey were Holmdel, Crawford Hill, the Deal Test Site, Lincroft, Long Branch, Neptune, Piscataway, Red Bank and Whippany. Of these, Murray Hill and Crawford Hill remain in existence; the largest grouping of people in the company was in Illinois, at Naperville-Lisle, in the Chicago area, which had the largest concentration of employees prior to 2001. There were groups of employees in Indianapolis, Indiana. Since 2001, many of the former locations closed; the Holmdel site, a 1.9 million square foot structure set on 473 acres, was closed in 2007.
The mirrored-glass building was designed by Eero Saarinen. In August 2013, Somerset Development bought the building, intending to redevelop it into a mixed commercial and residential project. A 2012 article expressed doubt on the success of the newly named Bell Works site however several large tenants had announced plans to move in through 2016 and 2017 Bell Laboratories was, is, regarded by many as the premier research facility of its type, developing a wide range of revolutionary technologies, including radio astronomy, the transistor, the laser, information theory, the operating system Unix, the programming languages C and C++, solar cells, the CCD, floating-gate MOSFET, a whole host of optical and wired communications