History of broadcasting
It is recognised that the first radio transmission was made from a temporary station set up by Guglielmo Marconi in 1895. This followed on from pioneering work in the field by a number of people including Alessandro Volta, André-Marie Ampère, Georg Ohm and James Clerk Maxwell; the radio broadcasting of music and talk intended to reach a dispersed audience started experimentally around 1905-1906, commercially around 1920 to 1923. VHF stations started 30 to 35 years later. In the early days, radio stations broadcast on the long wave, medium wave and short wave bands, on VHF and UHF. However, in the United Kingdom, Hungary and some other places, from as early as 1890 there was a system whereby news, live theatre, music hall, fiction readings, religious broadcasts, etc. were available in private homes via the conventional telephone line, with subscribers being supplied with a number of special, personalised headsets. In Britain this system was known as Electrophone, was available as early as 1895 or 1899 and up until 1926.
In Hungary, it was called Telefon Hírmondó, in France, Théâtrophone ). The Wikipedia Telefon Hírmondó page includes a 1907 program guide which looks remarkably similar to the types of schedules used by many broadcasting stations some 20 or 30 years later. By the 1950s every country had a broadcasting system one owned and operated by the government. Alternative modes included commercial radio, as in the United States. Today, most countries have evolved into a dual system, including the UK. By 1955 every family in North America and Western Europe, as well as Japan, had a radio. A dramatic change came in the 1960s with the introduction of small inexpensive portable transistor radio, the expanded ownership and usage. Access became universal across the world. Argentina was a world pioneer in broadcasting, being the third country in the world to make its first regular broadcasts in 1920, having been the first Spanish-speaking country in Latin America to offer daily radio broadcasts; the main stations were in Buenos Córdoba.
Among the historical facts related to Argentine radio, it can be mentioned that the first radio broadcast was made with the live broadcast of Richard Wagner's opera Parsifal from the Teatro Coliseo in Buenos Aires, on August 27, 1920, in charge of the Radio Argentina Society of Enrique Susini, César Guerrico, Miguel Mugica, Luis Romero and Ignacio Gómez, who installed a transmitting device on the roof of the building, for which they are remembered as "The crazy people on the roof". In 1921, the transmission of classical music became a daily occurrence; the following year, the assumption of President Marcelo Torcuato de Alvear was broadcast live. In September 1923 the famous "fight of the century" was issued between Luis Ángel Firpo and Jack Dempsey from the Polo Grounds in New York, in October of the following year the match between the Argentine and Uruguayan national teams was broadcast. At that time the first advertisements, called "reclames", were put on the air. At the end of the decade the radio drama was born.
In those years several radio stations arose, Culture, Mitre, Belgrano, Del Pueblo -, America-, Municipal, Porteña and Stentor. The introduction of the loudspeakers modified the listening conditions; the receiving apparatus was gaining an important place in the home. Meanwhile, the multiplication of the stations generated the first conflicts over the airwaves, which led to the first regulations on emission frequencies at the end of the 20s; the History of broadcasting in Australia has been shaped for over a century by the problem of communication across long distances, coupled with a strong base in a wealthy society with a deep taste for aural communications. Australia developed its own system, through its own engineers, retailers, entertainment services, news agencies; the government set up the first radio system, business interests marginalized the hobbyists and amateurs. The Labor Party was interested in radio because it allowed them to bypass the newspapers, which were controlled by the opposition.
Both parties agreed on the need for a national system, in 1932 set up the Australian Broadcasting Commission, as a government agency, separate from political interference. The first commercial broadcasters known as "B" class stations, were on the air as early as 1925; the number of stations remained dormant throughout World War II and in the post-war era. Australian radio hams can be traced to the early 1900s; the 1905 Wireless Telegraphy Act whilst acknowledging the existence of wireless telegraphy, brought all broadcasting matters in Australia under the control of the Federal Government. In 1906, the first official Morse code transmission in Australia was by the Marconi Company between Queenscliff and Devonport, Tasmania; the first broadcast of music was made during a demonstration on 13 August 1919 by Ernest Fisk of AWA – Amalgamated Wireless. A number of amateurs commenced broadcasting music in 1920 and 1921. Many other amateurs soon followed. 2CM w
University of Maine
The University of Maine is a public research university in Orono, United States. The university was established in 1865 as a land grant college and is the flagship university of the University of Maine System; the University of Maine is one of only a few land and space grant institutions in the nation. With an enrollment of 11,000 students, UMaine is the state's largest university and the only institution in Maine classified as a research university by the Carnegie Classification of Institutions of Higher Education; the University of Maine's athletic teams, nicknamed the Black Bears, are Maine's only Division I athletics program. Maine's men's ice hockey team; the University of Maine was founded in 1862 as a function of the Morrill Act, signed by President Lincoln. Established in 1865 as the Maine State College of Agriculture and the Mechanic Arts, the Maine College opened on September 21, 1868 and changed its name to the University of Maine in 1897. By 1871, curricula had been organized in Agriculture and electives.
The Maine Agricultural and Forest Experiment Station was founded as a division of the university in 1887. The university developed the Colleges of Life Sciences and Agriculture and Science, Arts and Sciences. In 1912 the Maine Cooperative Extension, which offers field educational programs for both adults and youths, was initiated; the School of Education was established in 1930 and received college status in 1958. The School of Business Administration was formed in 1958 and was granted college status in 1965. Women have been admitted into all curricula since 1872; the first master's degree was conferred in 1881. Since 1923 there has been a separate graduate school. Near the end of the 19th century, the university expanded its curriculum to place greater emphasis on liberal arts; as a result of this shift, faculty hired during the early 20th century included Caroline Colvin, chair of the history department and the nation's first woman to head a major university department. In 1906, The Senior Skull Honor Society was founded to "publicly recognize, formally reward, continually promote outstanding leadership and scholarship, exemplary citizenship within the University of Maine community."On April 16, 1925, 80 women met in Balentine Hall — faculty and undergraduate representatives — to plan a pledging of members to an inaugural honorary organization.
This organization was called "The All Maine Women" because only those women connected with the University of Maine were elected as members. On April 22, 1925, the new members were inducted into the honor society; when the University of Maine System was incorporated, in 1968, the school was renamed by the legislature over the objections of the faculty to the University of Maine at Orono. This was changed back to the University of Maine in 1986; the University of Maine is the flagship of the University of Maine System. The president of the university is Joan Ferrini-Mundy; the senior administration governs cooperatively with the Chancellor of the University of Maine system, James H. Page and the sixteen members of the University of Maine Board of Trustees; the Board of Trustees has full legal authority for the university system. It appoints the Chancellor and each university President, approves the establishment and elimination of academic programs, confers tenure on faculty members, sets tuition rates/operating budgets.
UMaine is one of a handful of colleges in the United States whose Student Government is incorporated. Student Government was formed in 1978 and incorporated in 1987, it is classified as a 501 not-for-profit corporation. It consists of a legislative branch, which passes resolutions, an executive branch, which helps organize on-campus entertainment and guest speakers, works with new and existing student organizations, performs other duties. Other organizations fall under the umbrella of Student Government Inc. including representative boards, community associations, many other student groups. The Maine Campus, the student newspaper, is incorporated and does not operate under or receive money from student government. Situated on Marsh Island, between the Penobscot and Stillwater rivers, the University of Maine is the nation's only land grant university on an island. Occupying the small city of Orono, population ~9,500, the 660-acre campus has an enrollment of 10,901 students; the campus has thirty-seven academic buildings, thirty administrative buildings, eighteen residence halls, eighteen specific laboratory facilities, fourteen Greek life houses, ten sports facilities, five museums, three dining facilities, two convenience stores, a student union, a cafe, a pub, an 87,000-square-foot state of the art recreation and fitness center, a 200'x200' air supported athletic/recreational dome.
In 1867, the university rejected a campus plan by landscape architect Frederick Law Olmsted, who designed Central Park in New York City and the White House grounds in Washington, D. C; the plan's broad concepts, including the Front Lawn, were adopted during the school's first fifty years, were oriented toward the Stillwater River. A second master plan was produced in 1932 by Carl Rust Parker of the Olmsted Brothers firm, which reoriented the campus center to the Mall, an open grassy area between the Raymond H. Fogler Library and the Memorial Gym; the Mall is further bordered by five academic halls. T
A computer network is a digital telecommunications network which allows nodes to share resources. In computer networks, computing devices exchange data with each other using connections between nodes; these data links are established over cable media such as wires or optic cables, or wireless media such as Wi-Fi. Network computer devices that originate and terminate the data are called network nodes. Nodes are identified by network addresses, can include hosts such as personal computers and servers, as well as networking hardware such as routers and switches. Two such devices can be said to be networked together when one device is able to exchange information with the other device, whether or not they have a direct connection to each other. In most cases, application-specific communications protocols are layered over other more general communications protocols; this formidable collection of information technology requires skilled network management to keep it all running reliably. Computer networks support an enormous number of applications and services such as access to the World Wide Web, digital video, digital audio, shared use of application and storage servers and fax machines, use of email and instant messaging applications as well as many others.
Computer networks differ in the transmission medium used to carry their signals, communications protocols to organize network traffic, the network's size, traffic control mechanism and organizational intent. The best-known computer network is the Internet; the chronology of significant computer-network developments includes: In the late 1950s, early networks of computers included the U. S. military radar system Semi-Automatic Ground Environment. In 1959, Anatolii Ivanovich Kitov proposed to the Central Committee of the Communist Party of the Soviet Union a detailed plan for the re-organisation of the control of the Soviet armed forces and of the Soviet economy on the basis of a network of computing centres, the OGAS. In 1960, the commercial airline reservation system semi-automatic business research environment went online with two connected mainframes. In 1963, J. C. R. Licklider sent a memorandum to office colleagues discussing the concept of the "Intergalactic Computer Network", a computer network intended to allow general communications among computer users.
In 1964, researchers at Dartmouth College developed the Dartmouth Time Sharing System for distributed users of large computer systems. The same year, at Massachusetts Institute of Technology, a research group supported by General Electric and Bell Labs used a computer to route and manage telephone connections. Throughout the 1960s, Paul Baran and Donald Davies independently developed the concept of packet switching to transfer information between computers over a network. Davies pioneered the implementation of the concept with the NPL network, a local area network at the National Physical Laboratory using a line speed of 768 kbit/s. In 1965, Western Electric introduced the first used telephone switch that implemented true computer control. In 1966, Thomas Marill and Lawrence G. Roberts published a paper on an experimental wide area network for computer time sharing. In 1969, the first four nodes of the ARPANET were connected using 50 kbit/s circuits between the University of California at Los Angeles, the Stanford Research Institute, the University of California at Santa Barbara, the University of Utah.
Leonard Kleinrock carried out theoretical work to model the performance of packet-switched networks, which underpinned the development of the ARPANET. His theoretical work on hierarchical routing in the late 1970s with student Farouk Kamoun remains critical to the operation of the Internet today. In 1972, commercial services using X.25 were deployed, used as an underlying infrastructure for expanding TCP/IP networks. In 1973, the French CYCLADES network was the first to make the hosts responsible for the reliable delivery of data, rather than this being a centralized service of the network itself. In 1973, Robert Metcalfe wrote a formal memo at Xerox PARC describing Ethernet, a networking system, based on the Aloha network, developed in the 1960s by Norman Abramson and colleagues at the University of Hawaii. In July 1976, Robert Metcalfe and David Boggs published their paper "Ethernet: Distributed Packet Switching for Local Computer Networks" and collaborated on several patents received in 1977 and 1978.
In 1979, Robert Metcalfe pursued making Ethernet an open standard. In 1976, John Murphy of Datapoint Corporation created ARCNET, a token-passing network first used to share storage devices. In 1995, the transmission speed capacity for Ethernet increased from 10 Mbit/s to 100 Mbit/s. By 1998, Ethernet supported transmission speeds of a Gigabit. Subsequently, higher speeds of up to 400 Gbit/s were added; the ability of Ethernet to scale is a contributing factor to its continued use. Computer networking may be considered a branch of electrical engineering, electronics engineering, telecommunications, computer science, information technology or computer engineering, since it relies upon the theoretical and practical application of the related disciplines. A computer network facilitates interpersonal communications allowing users to communicate efficiently and via various means: email, instant messaging, online chat, video telephone calls, video conferencing. A network allows sharing of computing resources.
Users may access and use resources provided by devices on the network, such as printing a document on a shared network printer or use of a shared storage device. A network allows sharing of files, and
History of mobile phones
The history of mobile phones covers mobile communication devices that connect wirelessly to the public switched telephone network. While the transmission of speech by radio has a long history, the first devices that were wireless and capable of connecting to the standard telephone network are much more recent; the first such devices were portable compared to today's compact hand-held devices, their use was clumsy. Along with the process of developing a more portable technology, a better interconnections system, drastic changes have taken place in both the networking of wireless communication and the prevalence of its use, with smartphones becoming common globally and a growing proportion of Internet access now done via mobile broadband. Before the devices existed that are now referred to as mobile phones or cell phones, there were some precursors. In 1908, a Professor Albert Jahnke and the Oakland Transcontinental Aerial Telephone and Power Company claimed to have developed a wireless telephone.
They were accused of fraud and the charge was dropped, but they do not seem to have proceeded with production. Beginning in 1918, the German railroad system tested wireless telephony on military trains between Berlin and Zossen. In 1924, public trials started with telephone connection on trains between Hamburg. In 1925, the company Zugtelephonie AG was founded to supply train telephony equipment and, in 1926, telephone service in trains of the Deutsche Reichsbahn and the German mail service on the route between Hamburg and Berlin was approved and offered to first-class travelers. Fiction anticipated the development of real world mobile telephones. In 1906, the English caricaturist Lewis Baumer published a cartoon in Punch magazine entitled "Forecasts for 1907" in which he showed a man and a woman in London's Hyde Park each separately engaged in gambling and dating on wireless telephony equipment. In 1926, the artist Karl Arnold created a visionary cartoon about the use of mobile phones in the street, in the picture "wireless telephony", published in the German satirical magazine Simplicissimus.
The Second World War made military use of radio telephony links. Hand-held radio transceivers have been available since the 1940s. Mobile telephones for automobiles became available from some telephone companies in the 1940s. Early devices were bulky, consumed large amounts of power, the network supported only a few simultaneous conversations. Modern cellular networks allow automatic and pervasive use of mobile phones for voice and data communications. In the United States, engineers from Bell Labs began work on a system to allow mobile users to place and receive telephone calls from automobiles, leading to the inauguration of mobile service on June 17th 1946 in St. Louis, Missouri. Shortly after, AT&T offered Mobile Telephone Service. A wide range of incompatible mobile telephone services offered limited coverage area and only a few available channels in urban areas; the introduction of cellular technology, which allowed re-use of frequencies many times in small adjacent areas covered by low powered transmitters, made widespread adoption of mobile telephones economically feasible.
In the USSR, Leonid Kupriyanovich, an engineer from Moscow, in 1957-1961 developed and presented a number of experimental pocket-sized communications radio. The weight of one model, presented in 1961, could fit on a palm. However, in the USSR the decision at first to develop the system of the automobile "Altai" phone was made. In 1965, the Bulgarian company "Radioelektronika" presented a mobile automatic phone combined with a base station at the Inforga-65 international exhibition in Moscow. Solutions of this phone were based on a system developed by Leonid Kupriyanovich. One base station, connected to one telephone wire line, could serve up to 15 customers; the advances in mobile telephony can be traced in successive generations from the early "0G" services like MTS and its successor Improved Mobile Telephone Service, to first-generation analog cellular network, second-generation digital cellular networks, third-generation broadband data services to the state-of-the-art, fourth-generation native-IP networks.
In 1949, AT&T commercialized Mobile Telephone Service. From its start in St. Louis, Missouri, in 1946, AT&T introduced Mobile Telephone Service to one hundred towns and highway corridors by 1948. Mobile Telephone Service was a rarity with only 5,000 customers placing about 30,000 calls each week. Calls were set up manually by an operator and the user had to depress a button on the handset to talk and release the button to listen; the call subscriber equipment weighed about 80 pounds Subscriber growth and revenue generation were hampered by the constraints of the technology. Because only three radio channels were available, only three customers in any given city could make mobile telephone calls at one time. Mobile Telephone Service was expensive, costing US$15 per month, plus $0.30–0.40 per local call, equivalent to about $176 per month and $3.50–4.75 per call. In the UK, there was a vehicle-based system called "Post Office Radiophone Service,", launched around the city of Manchester in 1959, although it required callers to speak to an operator, it was possible to be put through to any subscriber in Great Britain.
The service was extended to London in 1965 and other major cities in 1972. AT&T introduced the first major improvement to mobile telephony in 1965, giving the improved service the obvious name of Improved Mobile Telephone Service. IMTS used additional radio channels, allowing more simultaneous calls in a given geographic area, introduced customer dialing, eliminating manual call setup by an operator, reduced the size and weight of the subscriber equipment. Desp
The Persian Gulf is a mediterranean sea in Western Asia. The body of water is an extension of the Indian Ocean through the Strait of Hormuz and lies between Iran to the northeast and the Arabian Peninsula to the southwest; the Shatt al-Arab river delta forms the northwest shoreline. The body of water is and internationally known as the "Persian Gulf"; some Arab governments refer to it as the "Arabian Gulf" or "The Gulf", but neither term is recognized internationally. The name "Gulf of Iran" is used by the International Hydrographic Organization; the Persian Gulf was a battlefield of the 1980–1988 Iran–Iraq War, in which each side attacked the other's oil tankers. It is the namesake of the 1991 Gulf War, the air- and land-based conflict that followed Iraq's invasion of Kuwait; the gulf has many fishing grounds, extensive reefs, abundant pearl oysters, but its ecology has been damaged by industrialization and oil spills. The Persian Gulf resides in the Persian Gulf Basin, of Cenozoic origin and related to the subduction of the Arabian Plate under the Zagros Mountains.
The current flooding of the basin started 15,000 years ago due to rising sea levels of the Holocene glacial retreat. This inland sea of some 251,000 square kilometres is connected to the Gulf of Oman in the east by the Strait of Hormuz. In Iran this is called "Arvand Rood", where "Rood" means "river", its length is 989 kilometres, with Iran covering most of the northern coast and Saudi Arabia most of the southern coast. The Persian Gulf is about 56 km wide in the Strait of Hormuz; the waters are overall shallow, with a maximum depth of 90 metres and an average depth of 50 metres. Countries with a coastline on the Persian Gulf are: Iran. Various small islands lie within the Persian Gulf, some of which are the subject of territorial disputes between the states of the region; the International Hydrographic Organization defines the Persian Gulf's southern limit as "The Northwestern limit of Gulf of Oman". This limit is defined as "A line joining Ràs Limah on the coast of Arabia and Ràs al Kuh on the coast of Iran".
The gulf is connected to Indian Ocean through Strait of Hormuz. Writing the water balance budget for the Persian Gulf, the inputs are river discharges from Iran and Iraq, as well as precipitation over the sea, around 180mm/year in Qeshm Island; the evaporation of the sea is high, so that after considering river discharge and rain contributions, there is still a deficit of 416 cubic kilometers per year. This difference is supplied by currents at the Strait of Hormuz; the water from the Gulf has a higher salinity, therefore exits from the bottom of the Strait, while ocean water with less salinity flows in through the top. Another study revealed the following numbers for water exchanges for the Gulf: evaporation = -1.84m/year, precipitation = 0.08m/year, inflow from the Strait = 33.66m/year, outflow from the Strait = -32.11m/year, the balance is 0m/year. Data from different 3D computational fluid mechanics models with spatial resolution of 3 kilometers and depth each element equal to 1–10 meters are predominantly used in computer models.
The Persian Gulf and its coastal areas are the world's largest single source of crude oil, related industries dominate the region. Safaniya Oil Field, the world's largest offshore oilfield, is located in the Persian Gulf. Large gas finds have been made, with Qatar and Iran sharing a giant field across the territorial median line. Using this gas, Qatar has built up a substantial liquefied natural petrochemical industry. In 2002, the Persian Gulf nations of Bahrain, Iraq, Qatar, Saudi Arabia, the UAE produced about 25% of the world's oil, held nearly two-thirds of the world's crude oil reserves, about 35% of the world's natural gas reserves; the oil-rich countries that have a coastline on the Persian Gulf are referred to as the Persian Gulf States. Iraq's egress to the gulf is narrow and blockaded consisting of the marshy river delta of the Shatt al-Arab, which carries the waters of the Euphrates and the Tigris rivers, where the east bank is held by Iran. In 550 BC, the Achaemenid Empire established the first ancient empire in Persis, in the southwestern region of the Iranian plateau.
In the Greek sources, the body of water that bordered this province came to be known as the "Persian Gulf". During the years 550 to 330 BC, coinciding with the sovereignty of the Achaemenid Persian Empire over the Middle East area the whole part of the Persian Gulf and some parts of the Arabian Peninsula, the name of "Pars Sea" is found in the compiled written texts. In the travel account of Pythagoras, several chapters are related to description of his travels accompanied by the Achaemenid king Darius the Great, to Susa and Persepolis, the area is described. From among the writings of others in the same period, there is the inscription and engraving of Darius the Great, installed at junction of waters of Red Sea and the Nile river and the Rome river which belongs to t
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
History of the Internet
The history of the Internet begins with the development of electronic computers in the 1950s. Initial concepts of wide area networking originated in several computer science laboratories in the United States, United Kingdom, France; the U. S. Department of Defense awarded contracts as early as the 1960s, including for the development of the ARPANET project, directed by Robert Taylor and managed by Lawrence Roberts; the first message was sent over the ARPANET in 1969 from computer science Professor Leonard Kleinrock's laboratory at University of California, Los Angeles to the second network node at Stanford Research Institute. Packet switching networks such as the NPL network, ARPANET, Merit Network, CYCLADES, Telenet, were developed in the late 1960s and early 1970s using a variety of communications protocols. Donald Davies first demonstrated packet switching in 1967 at the National Physics Laboratory in the UK, which became a testbed for UK research for two decades; the ARPANET project led to the development of protocols for internetworking, in which multiple separate networks could be joined into a network of networks.
The Internet protocol suite was developed by Robert E. Kahn and Vint Cerf in the 1970s and became the standard networking protocol on the ARPANET, incorporating concepts from the French CYCLADES project directed by Louis Pouzin. In the early 1980s the NSF funded the establishment for national supercomputing centers at several universities, provided interconnectivity in 1986 with the NSFNET project, which created network access to the supercomputer sites in the United States from research and education organizations. Commercial Internet service providers began to emerge in the late 1980s; the ARPANET was decommissioned in 1990. Limited private connections to parts of the Internet by commercial entities emerged in several American cities by late 1989 and 1990, the NSFNET was decommissioned in 1995, removing the last restrictions on the use of the Internet to carry commercial traffic. In the 1980s, research at CERN in Switzerland by British computer scientist Tim Berners-Lee resulted in the World Wide Web, linking hypertext documents into an information system, accessible from any node on the network.
Since the mid-1990s, the Internet has had a revolutionary impact on culture and technology, including the rise of near-instant communication by electronic mail, instant messaging, voice over Internet Protocol telephone calls, two-way interactive video calls, the World Wide Web with its discussion forums, social networking, online shopping sites. The research and education community continues to develop and use advanced networks such as JANET in the United Kingdom and Internet2 in the United States. Increasing amounts of data are transmitted at higher and higher speeds over fiber optic networks operating at 1 Gbit/s, 10 Gbit/s, or more; the Internet's takeover of the global communication landscape was instant in historical terms: it only communicated 1% of the information flowing through two-way telecommunications networks in the year 1993 51% by 2000, more than 97% of the telecommunicated information by 2007. Today the Internet continues to grow, driven by greater amounts of online information, commerce and social networking.
However, the future of the global internet may be shaped by regional differences in the world. The concept of data communication – transmitting data between two different places through an electromagnetic medium such as radio or an electric wire – pre-dates the introduction of the first computers; such communication systems were limited to point to point communication between two end devices. Semaphore lines, telegraph systems and telex machines can be considered early precursors of this kind of communication; the Telegraph in the late 19th century was the first digital communication system. Fundamental theoretical work in data transmission and information theory was developed by Claude Shannon, Harry Nyquist, Ralph Hartley in the early 20th century. Early computers had remote terminals; as the technology evolved, new systems were devised to allow communication over longer distances or with higher speed that were necessary for the mainframe computer model. These technologies made it possible to exchange data between remote computers.
However, the point-to-point communication model was limited, as it did not allow for direct communication between any two arbitrary systems. The technology was considered unsafe for strategic and military use because there were no alternative paths for the communication in case of an enemy attack. With limited exceptions, the earliest computers were connected directly to terminals used by individual users in the same building or site; such networks became known as local area networks. Networking beyond this scope, known as wide area networks, emerged during the 1950s and became established during the 1960s. J. C. R. Licklider, Vice President at Bolt Beranek and Newman, Inc. proposed a global network in his January 1960 paper Man-Computer Symbiosis: A network of such centers, connected to one another by wide-band communication lines the functions of present-day libraries together with anticipated advances in information storage and retrieval and symbiotic functions suggested earlier in this paper In August 1962, Licklider and Welden Clark published the paper "On-Line Man-Computer Communication", one of the first descriptions of a networked future.
In October 1962, Licklider was hired by Jack Ruina as director of the newly established Information Processing Techniques Office w