World War II
World War II known as the Second World War, was a global war that lasted from 1939 to 1945. The vast majority of the world's countries—including all the great powers—eventually formed two opposing military alliances: the Allies and the Axis. A state of total war emerged, directly involving more than 100 million people from over 30 countries; the major participants threw their entire economic and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. World War II was the deadliest conflict in human history, marked by 50 to 85 million fatalities, most of whom were civilians in the Soviet Union and China, it included massacres, the genocide of the Holocaust, strategic bombing, premeditated death from starvation and disease, the only use of nuclear weapons in war. Japan, which aimed to dominate Asia and the Pacific, was at war with China by 1937, though neither side had declared war on the other. World War II is said to have begun on 1 September 1939, with the invasion of Poland by Germany and subsequent declarations of war on Germany by France and the United Kingdom.
From late 1939 to early 1941, in a series of campaigns and treaties, Germany conquered or controlled much of continental Europe, formed the Axis alliance with Italy and Japan. Under the Molotov–Ribbentrop Pact of August 1939, Germany and the Soviet Union partitioned and annexed territories of their European neighbours, Finland and the Baltic states. Following the onset of campaigns in North Africa and East Africa, the fall of France in mid 1940, the war continued between the European Axis powers and the British Empire. War in the Balkans, the aerial Battle of Britain, the Blitz, the long Battle of the Atlantic followed. On 22 June 1941, the European Axis powers launched an invasion of the Soviet Union, opening the largest land theatre of war in history; this Eastern Front trapped most crucially the German Wehrmacht, into a war of attrition. In December 1941, Japan launched a surprise attack on the United States as well as European colonies in the Pacific. Following an immediate U. S. declaration of war against Japan, supported by one from Great Britain, the European Axis powers declared war on the U.
S. in solidarity with their Japanese ally. Rapid Japanese conquests over much of the Western Pacific ensued, perceived by many in Asia as liberation from Western dominance and resulting in the support of several armies from defeated territories; the Axis advance in the Pacific halted in 1942. Key setbacks in 1943, which included a series of German defeats on the Eastern Front, the Allied invasions of Sicily and Italy, Allied victories in the Pacific, cost the Axis its initiative and forced it into strategic retreat on all fronts. In 1944, the Western Allies invaded German-occupied France, while the Soviet Union regained its territorial losses and turned toward Germany and its allies. During 1944 and 1945 the Japanese suffered major reverses in mainland Asia in Central China, South China and Burma, while the Allies crippled the Japanese Navy and captured key Western Pacific islands; the war in Europe concluded with an invasion of Germany by the Western Allies and the Soviet Union, culminating in the capture of Berlin by Soviet troops, the suicide of Adolf Hitler and the German unconditional surrender on 8 May 1945.
Following the Potsdam Declaration by the Allies on 26 July 1945 and the refusal of Japan to surrender under its terms, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki on 6 and 9 August respectively. With an invasion of the Japanese archipelago imminent, the possibility of additional atomic bombings, the Soviet entry into the war against Japan and its invasion of Manchuria, Japan announced its intention to surrender on 15 August 1945, cementing total victory in Asia for the Allies. Tribunals were set up by fiat by the Allies and war crimes trials were conducted in the wake of the war both against the Germans and the Japanese. World War II changed the political social structure of the globe; the United Nations was established to foster international co-operation and prevent future conflicts. The Soviet Union and United States emerged as rival superpowers, setting the stage for the nearly half-century long Cold War. In the wake of European devastation, the influence of its great powers waned, triggering the decolonisation of Africa and Asia.
Most countries whose industries had been damaged moved towards economic expansion. Political integration in Europe, emerged as an effort to end pre-war enmities and create a common identity; the start of the war in Europe is held to be 1 September 1939, beginning with the German invasion of Poland. The dates for the beginning of war in the Pacific include the start of the Second Sino-Japanese War on 7 July 1937, or the Japanese invasion of Manchuria on 19 September 1931. Others follow the British historian A. J. P. Taylor, who held that the Sino-Japanese War and war in Europe and its colonies occurred and the two wars merged in 1941; this article uses the conventional dating. Other starting dates sometimes used for World War II include the Italian invasion of Abyssinia on 3 October 1935; the British historian Antony Beevor views the beginning of World War II as the Battles of Khalkhin Gol fought between Japan and the fo
Texas is the second largest state in the United States by both area and population. Geographically located in the South Central region of the country, Texas shares borders with the U. S. states of Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, the Mexican states of Chihuahua, Nuevo León, Tamaulipas to the southwest, while the Gulf of Mexico is to the southeast. Houston is the most populous city in Texas and the fourth largest in the U. S. while San Antonio is the second-most populous in the state and seventh largest in the U. S. Dallas–Fort Worth and Greater Houston are the fourth and fifth largest metropolitan statistical areas in the country, respectively. Other major cities include Austin, the second-most populous state capital in the U. S. and El Paso. Texas is nicknamed "The Lone Star State" to signify its former status as an independent republic, as a reminder of the state's struggle for independence from Mexico; the "Lone Star" can be found on the Texan state seal.
The origin of Texas's name is from the word taysha. Due to its size and geologic features such as the Balcones Fault, Texas contains diverse landscapes common to both the U. S. Southern and Southwestern regions. Although Texas is popularly associated with the U. S. southwestern deserts, less than 10% of Texas's land area is desert. Most of the population centers are in areas of former prairies, grasslands and the coastline. Traveling from east to west, one can observe terrain that ranges from coastal swamps and piney woods, to rolling plains and rugged hills, the desert and mountains of the Big Bend; the term "six flags over Texas" refers to several nations. Spain was the first European country to claim the area of Texas. France held a short-lived colony. Mexico controlled the territory until 1836 when Texas won its independence, becoming an independent Republic. In 1845, Texas joined the union as the 28th state; the state's annexation set off a chain of events that led to the Mexican–American War in 1846.
A slave state before the American Civil War, Texas declared its secession from the U. S. in early 1861, joined the Confederate States of America on March 2nd of the same year. After the Civil War and the restoration of its representation in the federal government, Texas entered a long period of economic stagnation. Four major industries shaped the Texas economy prior to World War II: cattle and bison, cotton and oil. Before and after the U. S. Civil War the cattle industry, which Texas came to dominate, was a major economic driver for the state, thus creating the traditional image of the Texas cowboy. In the 19th century cotton and lumber grew to be major industries as the cattle industry became less lucrative, it was though, the discovery of major petroleum deposits that initiated an economic boom which became the driving force behind the economy for much of the 20th century. With strong investments in universities, Texas developed a diversified economy and high tech industry in the mid-20th century.
As of 2015, it is second on the list of the most Fortune 500 companies with 54. With a growing base of industry, the state leads in many industries, including agriculture, energy and electronics, biomedical sciences. Texas has led the U. S. in state export revenue since 2002, has the second-highest gross state product. If Texas were a sovereign state, it would be the 10th largest economy in the world; the name Texas, based on the Caddo word táyshaʼ "friend", was applied, in the spelling Tejas or Texas, by the Spanish to the Caddo themselves the Hasinai Confederacy, the final -s representing the Spanish plural. The Mission San Francisco de los Tejas was completed near the Hasinai village of Nabedaches in May 1690, in what is now Houston County, East Texas. During Spanish colonial rule, in the 18th century, the area was known as Nuevo Reino de Filipinas "New Kingdom of the Philippines", or as provincia de los Tejas "province of the Tejas" also provincia de Texas, "province of Texas", it was incorporated as provincia de Texas into the Mexican Empire in 1821, declared a republic in 1836.
The Royal Spanish Academy recognizes both spellings and Texas, as Spanish-language forms of the name of the U. S. State of Texas; the English pronunciation with /ks/ is unetymological, based in the value of the letter x in historical Spanish orthography. Alternative etymologies of the name advanced in the late 19th century connected the Spanish teja "rooftile", the plural tejas being used to designate indigenous Pueblo settlements. A 1760s map by Jacques-Nicolas Bellin shows a village named Teijas on Trinity River, close to the site of modern Crockett. Texas is the second-largest U. S. state, with an area of 268,820 square miles. Though 10% larger than France and twice as large as Germany or Japan, it ranks only 27th worldwide amongst country subdivisions by size. If it were an independent country, Texas would be the 40th largest behind Zambia. Texas is in the south central part of the United States of America. Three of its borders are defined by rivers; the Rio Grande forms a natural border with the Mexican states of Chihuahua, Nuevo León, Tamaulipas to the south.
The Red River forms a natural border with Arkansas to the north. The Sabine River forms a natural border with Louisiana to the east; the Texas Panhandle has an eastern border with Oklahoma at 100° W, a northern border with Oklahoma at 36°30' N and a western
University of Texas at Austin
The University of Texas at Austin is a public research university in Austin, Texas. It is the flagship institution of the University of Texas System; the University of Texas was inducted into the Association of American Universities in 1929, becoming only the third university in the American South to be elected. The institution has the nation's eighth-largest single-campus enrollment, with over 50,000 undergraduate and graduate students and over 24,000 faculty and staff. A Public Ivy, it is a major center for academic research, with research expenditures exceeding $615 million for the 2016–2017 school year; the university houses seven museums and seventeen libraries, including the Lyndon Baines Johnson Library and Museum and the Blanton Museum of Art, operates various auxiliary research facilities, such as the J. J. Pickle Research Campus and the McDonald Observatory. Among university faculty are recipients of the Nobel Prize, Pulitzer Prize, the Wolf Prize, the Primetime Emmy Award, the Turing Award, the National Medal of Science, as well as many other awards.
As of October 2018, 11 Nobel Prize winners, 2 Turing Award winners and 1 Fields medalist have been affiliated with the school as alumni, faculty members or researchers. Student athletes are members of the Big 12 Conference, its Longhorn Network is the only sports network featuring the college sports of a single university. The Longhorns have won four NCAA Division I National Football Championships, six NCAA Division I National Baseball Championships, thirteen NCAA Division I National Men's Swimming and Diving Championships, has claimed more titles in men's and women's sports than any other school in the Big 12 since the league was founded in 1996; the first mention of a public university in Texas can be traced to the 1827 constitution for the Mexican state of Coahuila y Tejas. Although Title 6, Article 217 of the Constitution promised to establish public education in the arts and sciences, no action was taken by the Mexican government. After Texas obtained its independence from Mexico in 1836, the Texas Congress adopted the Constitution of the Republic, under Section 5 of its General Provisions, stated "It shall be the duty of Congress, as soon as circumstances will permit, to provide, by law, a general system of education."On April 18, 1838, "An Act to Establish the University of Texas" was referred to a special committee of the Texas Congress, but was not reported back for further action.
On January 26, 1839, the Texas Congress agreed to set aside fifty leagues of land—approximately 288,000 acres —towards the establishment of a publicly funded university. In addition, 40 acres in the new capital of Austin were reserved and designated "College Hill." In 1845, Texas was annexed into the United States. The state's Constitution of 1845 failed to mention higher education. On February 11, 1858, the Seventh Texas Legislature approved O. B. 102, an act to establish the University of Texas, which set aside $100,000 in United States bonds toward construction of the state's first publicly funded university. The legislature designated land reserved for the encouragement of railroad construction toward the university's endowment. On January 31, 1860, the state legislature, wanting to avoid raising taxes, passed an act authorizing the money set aside for the University of Texas to be used for frontier defense in west Texas to protect settlers from Indian attacks. Texas's secession from the Union and the American Civil War delayed repayment of the borrowed monies.
At the end of the Civil War in 1865, The University of Texas's endowment was just over $16,000 in warrants and nothing substantive had been done to organize the university's operations. This effort to establish a University was again mandated by Article 7, Section 10 of the Texas Constitution of 1876 which directed the legislature to "establish and provide for the maintenance and direction of a university of the first class, to be located by a vote of the people of this State, styled "The University of Texas."Additionally, Article 7, Section 11 of the 1876 Constitution established the Permanent University Fund, a sovereign wealth fund managed by the Board of Regents of the University of Texas and dedicated for the maintenance of the university. Because some state legislators perceived an extravagance in the construction of academic buildings of other universities, Article 7, Section 14 of the Constitution expressly prohibited the legislature from using the state's general revenue to fund construction of university buildings.
Funds for constructing university buildings had to come from the university's endowment or from private gifts to the university, but the university's operating expenses could come from the state's general revenues. The 1876 Constitution revoked the endowment of the railroad lands of the Act of 1858, but dedicated 1,000,000 acres of land, along with other property appropriated for the university, to the Permanent University Fund; this was to the detriment of the university as the lands the Constitution of 1876 granted the university represented less than 5% of the value of the lands granted to the university under the Act of 1858. The more valuable lands reverted to the fund to support general educat
Sweetwater is a municipality in and the seat of Nolan County, United States. It is 236 miles southeast of Amarillo and 181 miles west of Fort Worth; the population was 10,906 at the 2010 census. Sweetwater received a U. S. post office in 1879. The Texas and Pacific Railway started service in 1881, with the first train arriving on March 12 of that year, beginning Sweetwater's long history as a railroad town. To encourage the railroads, Sweetwater increased its water supply by building a small town lake in 1898, three larger lakes thereafter. Construction began on the Kansas City and Orient Railway in 1903. Sweetwater became a railroad town, with homes built along the rail line. Rail passenger service was discontinued in 1969. Gulf Refinery operated there from 1929 to 1954, at one time the town was a large telegraph center; the International Harvester Company operated a factory in Sweetwater from 1920 to 1950. Gypsum plants, apparel manufacturers, cement plants, cotton compresses, a cottonseed oil mill, packing companies were among the nearly 250 businesses operating there from the 1970s.
Many still operate today. Sweetwater remains a production hub for such commodities as cotton and cattle; the population of Sweetwater has remained steady between 11,000 and 13,000 since 1940. At Sweetwater during World War II, one class of British RAF pilots was trained before the air field was converted for training American women pilots; the Women Airforce Service Pilots were trained under the direction of famed aviator Jacqueline Cochran at Sweetwater's Avenger Field. These WASPs were the first women to fly American military aircraft; the military airstrip was closed at the end of the war. Pilots flying over Sweetwater can still land at Avenger Field – the Sweetwater Airport; the National WASP WWII Museum is located at Avenger Field. The WASP women were not recognized for having served in the armed forces until 1977, after U. S. Senator Barry M. Goldwater of Arizona and Colonel Bruce Arnold, late son of General Hap Arnold, gained their official recognition as military veterans. In 1970, the field was developed for Texas State Technical College in Sweetwater.
Sweetwater has a Pioneer Museum, with display rooms depicting the lives of early settlers. It has extensive photograph files and ranch exhibits, Indian artifacts, WASP exhibits; the local newspaper, Sweetwater Reporter, was founded in 1881. An historic early 20th-century movie theater is in full use; the municipal auditorium, where Elvis Presley once performed, continues to feature live acts. Sweetwater has a hospital, founded in 1976. Sports include access to a large public swimming pool and there is an 18-hole golf course.. Public fishing and recreational facilities are located at Lake Sweetwater. First Baptist Church had one of the earliest congregations in Sweetwater, it continues to thrive. Parts of the south side of Sweetwater were devastated by an estimated EF3 tornado that swept through town early in the morning of April 19, 1986. Sweetwater is the center of the leading wind power generation region of the Western Hemisphere, it is sometimes incorrectly called the "Wind Turbine Capital of Texas."
The largest wind farm in Texas is Roscoe Wind Farm. In 2009 about 1,330 direct wind-related jobs were created in Nolan County alone, where the industry generated $18,000,000 in annual landowner royalties and over $12,000,000 in annual local school taxes. Special events include the world's largest rattlesnake round-up, held annually since 1958 by the Sweetwater Jaycees on the second weekend in March, it is held along with a gun and coin show hosted by the Sweetwater Rifle and Pistol Club, founded in the 1940s. According to Tom Henderson, a member of the Sweetwater Chamber of Commerce Board of Directors: "If you're bored here, it's your own fault." Sweetwater is located at 32°28′5″N 100°24′26″W. According to the United States Census Bureau, the city has a total area of 10.0 square miles, all of it land. Sweetwater is the center of the Western Hemisphere's leading wind power generation region and West Texas has more than 4,000 MW of operational wind energy. Nolan County alone would rank as the eighth-largest "nation" in terms of wind energy generation - with more than 1,500 MW installed.
Climate type occurs on the periphery of the true deserts in low-latitude semiarid steppe regions. The Köppen climate classification subtype for this climate is BSk; as of the census of 2000, 11,415 people, 4,545 households, 3,017 families resided in the city. The population density was 1,139.4 people per square mile. There were 5,202 housing units at an average density of 519.2 per square mile. The racial makeup of the city was 75.29% White, 5.83% African American, 0.58% Native American, 0.32% Asian, 0.07% Pacific Islander, 15.71% from other races, 2.21% from two or more races. Hispanics or Latinos of any race were 31.70% of the population. In the city, the population was distributed as 28.1% under the age of 18, 8.9% from 18 to 24, 26.0% from 25 to 44, 21.1% from 45 to 64, 15.8% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 91.1 males. For every 100 females age 18 and over, there were 86.7 males. The median income for a household in the city was $24,293, for a family was $29,953.
Males had a median income of $27,722 versus $18,064 for females. The per capita income for the city was $13,065. About 20.5% of families and 23.7% of the population were below the poverty line, including 31.5% of those under age 18 and 22.0% of those age 65 or over. The City of Sweetwater is served by the Sweetwater Independent School District, which includes J. P. Cowen Ear
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
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
Mathematics includes the study of such topics as quantity, structure and change. Mathematicians use patterns to formulate new conjectures; when mathematical structures are good models of real phenomena mathematical reasoning can provide insight or predictions about nature. Through the use of abstraction and logic, mathematics developed from counting, calculation and the systematic study of the shapes and motions of physical objects. Practical mathematics has been a human activity from as far back; the research required to solve mathematical problems can take years or centuries of sustained inquiry. Rigorous arguments first appeared in Greek mathematics, most notably in Euclid's Elements. Since the pioneering work of Giuseppe Peano, David Hilbert, others on axiomatic systems in the late 19th century, it has become customary to view mathematical research as establishing truth by rigorous deduction from appropriately chosen axioms and definitions. Mathematics developed at a slow pace until the Renaissance, when mathematical innovations interacting with new scientific discoveries led to a rapid increase in the rate of mathematical discovery that has continued to the present day.
Mathematics is essential in many fields, including natural science, medicine and the social sciences. Applied mathematics has led to new mathematical disciplines, such as statistics and game theory. Mathematicians engage in pure mathematics without having any application in mind, but practical applications for what began as pure mathematics are discovered later; the history of mathematics can be seen as an ever-increasing series of abstractions. The first abstraction, shared by many animals, was that of numbers: the realization that a collection of two apples and a collection of two oranges have something in common, namely quantity of their members; as evidenced by tallies found on bone, in addition to recognizing how to count physical objects, prehistoric peoples may have recognized how to count abstract quantities, like time – days, years. Evidence for more complex mathematics does not appear until around 3000 BC, when the Babylonians and Egyptians began using arithmetic and geometry for taxation and other financial calculations, for building and construction, for astronomy.
The most ancient mathematical texts from Mesopotamia and Egypt are from 2000–1800 BC. Many early texts mention Pythagorean triples and so, by inference, the Pythagorean theorem seems to be the most ancient and widespread mathematical development after basic arithmetic and geometry, it is in Babylonian mathematics that elementary arithmetic first appear in the archaeological record. The Babylonians possessed a place-value system, used a sexagesimal numeral system, still in use today for measuring angles and time. Beginning in the 6th century BC with the Pythagoreans, the Ancient Greeks began a systematic study of mathematics as a subject in its own right with Greek mathematics. Around 300 BC, Euclid introduced the axiomatic method still used in mathematics today, consisting of definition, axiom and proof, his textbook Elements is considered the most successful and influential textbook of all time. The greatest mathematician of antiquity is held to be Archimedes of Syracuse, he developed formulas for calculating the surface area and volume of solids of revolution and used the method of exhaustion to calculate the area under the arc of a parabola with the summation of an infinite series, in a manner not too dissimilar from modern calculus.
Other notable achievements of Greek mathematics are conic sections, trigonometry (Hipparchus of Nicaea, the beginnings of algebra. The Hindu–Arabic numeral system and the rules for the use of its operations, in use throughout the world today, evolved over the course of the first millennium AD in India and were transmitted to the Western world via Islamic mathematics. Other notable developments of Indian mathematics include the modern definition of sine and cosine, an early form of infinite series. During the Golden Age of Islam during the 9th and 10th centuries, mathematics saw many important innovations building on Greek mathematics; the most notable achievement of Islamic mathematics was the development of algebra. Other notable achievements of the Islamic period are advances in spherical trigonometry and the addition of the decimal point to the Arabic numeral system. Many notable mathematicians from this period were Persian, such as Al-Khwarismi, Omar Khayyam and Sharaf al-Dīn al-Ṭūsī. During the early modern period, mathematics began to develop at an accelerating pace in Western Europe.
The development of calculus by Newton and Leibniz in the 17th century revolutionized mathematics. Leonhard Euler was the most notable mathematician of the 18th century, contributing numerous theorems and discoveries; the foremost mathematician of the 19th century was the German mathematician Carl Friedrich Gauss, who made numerous contributions to fields such as algebra, differential geometry, matrix theory, number theory, statistics. In the early 20th century, Kurt Gödel transformed mathematics by publishing his incompleteness theorems, which show that any axiomatic system, consistent will contain unprovable propositions. Mathematics has since been extended, there has been a fruitful interaction between mathematics and science, to