An industry is the production of goods or related services within an economy. The major source of revenue of a group or company is the indicator of its relevant industry; when a large group has multiple sources of revenue generation, it is considered to be working in different industries. Manufacturing industry became a key sector of production and labour in European and North American countries during the Industrial Revolution, upsetting previous mercantile and feudal economies; this came through many successive rapid advances in technology, such as the production of steel and coal. Following the Industrial Revolution a third of the economic output comes from manufacturing industries. Many developed countries and many developing/semi-developed countries depend on manufacturing industry. Slavery, the practice of utilizing forced labor to produce goods and services, has occurred since antiquity throughout the world as a means of low-cost production, it produces goods for which profit depends on economies of scale those for which labor was simple and easy to supervise.
International law has declared slavery illegal. Guilds, associations of artisans and merchants, oversee the production and distribution of a particular good. Guilds have their roots in the Roman Empire as collegia Membership in these early guilds was voluntary; the Roman collegia did not survive the fall of Rome. In the early middle ages, guilds once again began to emerge in Europe, reaching a degree of maturity by the beginning of the 14th century. While few guilds remain today, some modern labor structures resemble those of traditional guilds. Other guilds, such as the SAG-AFTRA act as trade unions rather than as classical guilds. Professor Sheilagh Ogilvie claims that guilds negatively affected quality and innovation in areas that they were present; the industrial revolution saw the development and popularization of mechanized means of production as a replacement for hand production. The industrial revolution played a role in the abolition of slavery in North America; the Industrial Revolution led to the development of factories for large-scale production with consequent changes in society.
The factories were steam-powered, but transitioned to electricity once an electrical grid was developed. The mechanized assembly line was introduced to assemble parts in a repeatable fashion, with individual workers performing specific steps during the process; this led to significant increases in efficiency. Automation was used to replace human operators; this process has accelerated with the development of the robot. Certain manufacturing industries have gone into a decline due to various economic factors, including the development of replacement technology or the loss of competitive advantage. An example of the former is the decline in carriage manufacturing when the automobile was mass-produced. A recent trend has been the migration of prosperous, industrialized nations towards a post-industrial society; this is manifested by an increase in the service sector at the expense of manufacturing, the development of an information-based economy, the so-called informational revolution. In a post-industrial society, manufacturers relocate to more profitable locations through a process of off-shoring.
Measurements of manufacturing industries outputs and economic effect are not stable. Traditionally, success has been measured in the number of jobs created; the reduced number of employees in the manufacturing sector has been assumed to result from a decline in the competitiveness of the sector, or the introduction of the lean manufacturing process. Related to this change is the upgrading of the quality of the product being manufactured. While it is possible to produce a low-technology product with low-skill labour, the ability to manufacture high-technology products well is dependent on a skilled staff. An industrial society is a society driven by the use of technology to enable mass production, supporting a large population with a high capacity for division of labour. Today, industry is an important part of nations. A government must have some kind of industrial policy, regulating industrial placement, industrial pollution and industrial labour. In an industrial society, industry employs a major part of the population.
This occurs in the manufacturing sector. A labour union is an organization of workers who have banded together to achieve common goals in key areas such as wages and other working conditions; the trade union, through its leadership, bargains with the employer on behalf of union members and negotiates labour contracts with employers. This movement first rose among industrial workers; the Industrial Revolution changed warfare, with mass-produced weaponry and supplies, machine-powered transportation, the total war concept and weapons of mass destruction. Early instances of industrial warfare were the Crimean War and the American Civil War, but its full potential showed during the world wars. See military-industrial complex, arms industries, military industry and modern warfare. Industries portal Industry information North American Industry Classification System North American Product Classification System Outline of industry Standard Industrial Classification Krahn, Harvey J. and Graham S. Lowe.
Work and Canadian Society. Second ed. Scarborough, Ont.: Nelson Canada, 1993. Xii, 430 pp. ISBN 0-17-603540-0 Media related to Industries at Wikimedia Commons Quotations related to industry at Wikiquote
The United Kingdom the United Kingdom of Great Britain and Northern Ireland, sometimes referred to as Britain, is a sovereign country located off the north-western coast of the European mainland. The United Kingdom includes the island of Great Britain, the north-eastern part of the island of Ireland, many smaller islands. Northern Ireland is the only part of the United Kingdom that shares a land border with another sovereign state, the Republic of Ireland. Apart from this land border, the United Kingdom is surrounded by the Atlantic Ocean, with the North Sea to the east, the English Channel to the south and the Celtic Sea to the south-west, giving it the 12th-longest coastline in the world; the Irish Sea lies between Great Ireland. With an area of 242,500 square kilometres, the United Kingdom is the 78th-largest sovereign state in the world, it is the 22nd-most populous country, with an estimated 66.0 million inhabitants in 2017. The UK is constitutional monarchy; the current monarch is Queen Elizabeth II, who has reigned since 1952, making her the longest-serving current head of state.
The United Kingdom's capital and largest city is London, a global city and financial centre with an urban area population of 10.3 million. Other major urban areas in the UK include Greater Manchester, the West Midlands and West Yorkshire conurbations, Greater Glasgow and the Liverpool Built-up Area; the United Kingdom consists of four constituent countries: England, Scotland and Northern Ireland. Their capitals are London, Edinburgh and Belfast, respectively. Apart from England, the countries have their own devolved governments, each with varying powers, but such power is delegated by the Parliament of the United Kingdom, which may enact laws unilaterally altering or abolishing devolution; the nearby Isle of Man, Bailiwick of Guernsey and Bailiwick of Jersey are not part of the UK, being Crown dependencies with the British Government responsible for defence and international representation. The medieval conquest and subsequent annexation of Wales by the Kingdom of England, followed by the union between England and Scotland in 1707 to form the Kingdom of Great Britain, the union in 1801 of Great Britain with the Kingdom of Ireland created the United Kingdom of Great Britain and Ireland.
Five-sixths of Ireland seceded from the UK in 1922, leaving the present formulation of the United Kingdom of Great Britain and Northern Ireland. There are fourteen British Overseas Territories, the remnants of the British Empire which, at its height in the 1920s, encompassed a quarter of the world's land mass and was the largest empire in history. British influence can be observed in the language and political systems of many of its former colonies; the United Kingdom is a developed country and has the world's fifth-largest economy by nominal GDP and ninth-largest economy by purchasing power parity. It has a high-income economy and has a high Human Development Index rating, ranking 14th in the world, it was the world's first industrialised country and the world's foremost power during the 19th and early 20th centuries. The UK remains a great power, with considerable economic, military and political influence internationally, it is sixth in military expenditure in the world. It has been a permanent member of the United Nations Security Council since its first session in 1946.
It has been a leading member state of the European Union and its predecessor, the European Economic Community, since 1973. The United Kingdom is a member of the Commonwealth of Nations, the Council of Europe, the G7, the G20, NATO, the Organisation for Economic Co-operation and Development and the World Trade Organization; the 1707 Acts of Union declared that the kingdoms of England and Scotland were "United into One Kingdom by the Name of Great Britain". The term "United Kingdom" has been used as a description for the former kingdom of Great Britain, although its official name from 1707 to 1800 was "Great Britain"; the Acts of Union 1800 united the kingdom of Great Britain and the kingdom of Ireland in 1801, forming the United Kingdom of Great Britain and Ireland. Following the partition of Ireland and the independence of the Irish Free State in 1922, which left Northern Ireland as the only part of the island of Ireland within the United Kingdom, the name was changed to the "United Kingdom of Great Britain and Northern Ireland".
Although the United Kingdom is a sovereign country, Scotland and Northern Ireland are widely referred to as countries. The UK Prime Minister's website has used the phrase "countries within a country" to describe the United Kingdom; some statistical summaries, such as those for the twelve NUTS 1 regions of the United Kingdom refer to Scotland and Northern Ireland as "regions". Northern Ireland is referred to as a "province". With regard to Northern Ireland, the descriptive name used "can be controversial, with the choice revealing one's political preferences"; the term "Great Britain" conventionally refers to the island of Great Britain, or politically to England and Wales in combination. However, it is sometimes used as a loose synonym for the United Kingdom as a whole; the term "Britain" is used both as a synonym for Great Britain, as a synonym for the United Kingdom. Usage is mixed, with the BBC preferring to use Britain as shorthand only for Great Britain and the UK Government, while accepting that both terms refer to the United K
The European Union is a political and economic union of 28 member states that are located in Europe. It has an area of an estimated population of about 513 million; the EU has developed an internal single market through a standardised system of laws that apply in all member states in those matters, only those matters, where members have agreed to act as one. EU policies aim to ensure the free movement of people, goods and capital within the internal market, enact legislation in justice and home affairs and maintain common policies on trade, agriculture and regional development. For travel within the Schengen Area, passport controls have been abolished. A monetary union was established in 1999 and came into full force in 2002 and is composed of 19 EU member states which use the euro currency; the EU and European citizenship were established when the Maastricht Treaty came into force in 1993. The EU traces its origins to the European Coal and Steel Community and the European Economic Community, established by the 1951 Treaty of Paris and 1957 Treaty of Rome.
The original members of what came to be known as the European Communities were the Inner Six: Belgium, Italy, the Netherlands, West Germany. The Communities and its successors have grown in size by the accession of new member states and in power by the addition of policy areas to its remit; the latest major amendment to the constitutional basis of the EU, the Treaty of Lisbon, came into force in 2009. While no member state has left the EU or its antecedent organisations, the United Kingdom signified the intention to leave after a membership referendum in June 2016 and is negotiating its withdrawal. Covering 7.3% of the world population, the EU in 2017 generated a nominal gross domestic product of 19.670 trillion US dollars, constituting 24.6% of global nominal GDP. Additionally, all 28 EU countries have a high Human Development Index, according to the United Nations Development Programme. In 2012, the EU was awarded the Nobel Peace Prize. Through the Common Foreign and Security Policy, the EU has developed a role in external relations and defence.
The union maintains permanent diplomatic missions throughout the world and represents itself at the United Nations, the World Trade Organization, the G7 and the G20. Because of its global influence, the European Union has been described as an emerging superpower. During the centuries following the fall of Rome in 476, several European States viewed themselves as translatio imperii of the defunct Roman Empire: the Frankish Empire and the Holy Roman Empire were thereby attempts to resurrect Rome in the West; this political philosophy of a supra-national rule over the continent, similar to the example of the ancient Roman Empire, resulted in the early Middle Ages in the concept of a renovatio imperii, either in the forms of the Reichsidee or the religiously inspired Imperium Christianum. Medieval Christendom and the political power of the Papacy are cited as conducive to European integration and unity. In the oriental parts of the continent, the Russian Tsardom, the Empire, declared Moscow to be Third Rome and inheritor of the Eastern tradition after the fall of Constantinople in 1453.
The gap between Greek East and Latin West had been widened by the political scission of the Roman Empire in the 4th century and the Great Schism of 1054. Pan-European political thought emerged during the 19th century, inspired by the liberal ideas of the French and American Revolutions after the demise of Napoléon's Empire. In the decades following the outcomes of the Congress of Vienna, ideals of European unity flourished across the continent in the writings of Wojciech Jastrzębowski, Giuseppe Mazzini or Theodore de Korwin Szymanowski; the term United States of Europe was used at that time by Victor Hugo during a speech at the International Peace Congress held in Paris in 1849: A day will come when all nations on our continent will form a European brotherhood... A day will come when we shall see... the United States of America and the United States of Europe face to face, reaching out for each other across the seas. During the interwar period, the consciousness that national markets in Europe were interdependent though confrontational, along with the observation of a larger and growing US market on the other side of the ocean, nourished the urge for the economic integration of the continent.
In 1920, advocating the creation of a European economic union, British economist John Maynard Keynes wrote that "a Free Trade Union should be established... to impose no protectionist tariffs whatever against the produce of other members of the Union." During the same decade, Richard von Coudenhove-Kalergi, one of the first to imagine of a modern political union of Europe, founded the Pan-Europa Movement. His ideas influenced his contemporaries, among which Prime Minister of France Aristide Briand. In 1929, the latter gave a speech in favour of a European Union before the assembly of the League of Nations, precursor of the United Nations. In a radio address in March 1943, with war still raging, Britain's leader Sir Winston Churchill spoke warmly of "restoring the true greatness of Europe" once victory had been achieved, mused on the post-war creation of a "Council of Europe" which would bring the European nations together to build peace. After World War II, European integration was seen as an antidote to the extreme nationalism which had devastated the continent.
In a speech delivered on 19
Tourism is travel for pleasure or business. Tourism may be international, or within the traveller's country; the World Tourism Organization defines tourism more in terms which go "beyond the common perception of tourism as being limited to holiday activity only", as people "traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure and not less than 24 hours and other purposes". Tourism can be domestic or international, international tourism has both incoming and outgoing implications on a country's balance of payments. Tourism suffered as a result of a strong economic slowdown of the late-2000s recession, between the second half of 2008 and the end of 2009, the outbreak of the H1N1 influenza virus, but recovered. International tourism receipts grew to US$1.03 trillion in 2005, corresponding to an increase in real terms of 3.8% from 2010. International tourist arrivals surpassed the milestone of 1 billion tourists globally for the first time in 2012, emerging markets such as China and Brazil had increased their spending over the previous decade.
The ITB Berlin is the world's leading tourism trade fair. Global tourism accounts for ca. 8% of global greenhouse gas emissions. The word tourist was used in 1772 and tourism in 1811, it is formed from the word tour, derived from Old English turian, from Old French torner, from Latin tornare. Tourism has become an important source of income for many regions and entire countries; the Manila Declaration on World Tourism of 1980 recognized its importance as "an activity essential to the life of nations because of its direct effects on the social, cultural and economic sectors of national societies and on their international relations."Tourism brings large amounts of income into a local economy in the form of payment for goods and services needed by tourists, accounting as of 2011 for 30% of the world's trade in services, for 6% of overall exports of goods and services. It generates opportunities for employment in the service sector of the economy associated with tourism; the hospitality industries which benefit from tourism include transportation services.
This is in addition to goods bought by tourists, including souvenirs. On the flip-side, tourism can degrade sour relationships between host and guest. In 1936, the League of Nations defined a foreign tourist as "someone traveling abroad for at least twenty-four hours", its successor, the United Nations, amended this definition in 1945, by including a maximum stay of six months. In 1941, Hunziker and Kraft defined tourism as "the sum of the phenomena and relationships arising from the travel and stay of non-residents, insofar as they do not lead to permanent residence and are not connected with any earning activity." In 1976, the Tourism Society of England's definition was: "Tourism is the temporary, short-term movement of people to destinations outside the places where they live and work and their activities during the stay at each destination. It includes movements for all purposes." In 1981, the International Association of Scientific Experts in Tourism defined tourism in terms of particular activities chosen and undertaken outside the home.
In 1994, the United Nations identified three forms of tourism in its Recommendations on Tourism Statistics: Domestic tourism, involving residents of the given country traveling only within this country Inbound tourism, involving non-residents traveling in the given country Outbound tourism, involving residents traveling in another countryThe terms tourism and travel are sometimes used interchangeably. In this context, travel implies a more purposeful journey; the terms tourism and tourist are sometimes used pejoratively, to imply a shallow interest in the cultures or locations visited. By contrast, traveler is used as a sign of distinction; the sociology of tourism has studied the cultural values underpinning these distinctions and their implications for class relations. International tourist arrivals reached 1.035 billion in 2012, up from over 996 million in 2011, 952 million in 2010. In 2011 and 2012, international travel demand continued to recover from the losses resulting from the late-2000s recession, where tourism suffered a strong slowdown from the second half of 2008 through the end of 2009.
After a 5% increase in the first half of 2008, growth in international tourist arrivals moved into negative territory in the second half of 2008, ended up only 2% for the year, compared to a 7% increase in 2007. The negative trend intensified during 2009, exacerbated in some countries due to the outbreak of the H1N1 influenza virus, resulting in a worldwide decline of 4.2% in 2009 to 880 million international tourists arrivals, a 5.7% decline in international tourism receipts. The World Tourism Organization reports the following ten destinations as the most visited in terms of the number of international travelers in 2017. International tourism receipts grew to US$1.26 Trillion in 2015, corresponding to an increase in real terms of 4.4% from 2014. The World Tourism Organization reports the following entities as the top ten tourism earners for the year 2015: The World Tourism Organizati
Telecommunication is the transmission of signs, messages, writings and sounds or information of any nature by wire, optical or other electromagnetic systems. Telecommunication occurs when the exchange of information between communication participants includes the use of technology, it is transmitted either electrically over physical media, such as cables, or via electromagnetic radiation. Such transmission paths are divided into communication channels which afford the advantages of multiplexing. Since the Latin term communicatio is considered the social process of information exchange, the term telecommunications is used in its plural form because it involves many different technologies. Early means of communicating over a distance included visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, optical heliographs. Other examples of pre-modern long-distance communication included audio messages such as coded drumbeats, lung-blown horns, loud whistles. 20th- and 21st-century technologies for long-distance communication involve electrical and electromagnetic technologies, such as telegraph and teleprinter, radio, microwave transmission, fiber optics, communications satellites.
A revolution in wireless communication began in the first decade of the 20th century with the pioneering developments in radio communications by Guglielmo Marconi, who won the Nobel Prize in Physics in 1909, other notable pioneering inventors and developers in the field of electrical and electronic telecommunications. These included Charles Wheatstone and Samuel Morse, Alexander Graham Bell, Edwin Armstrong and Lee de Forest, as well as Vladimir K. Zworykin, John Logie Baird and Philo Farnsworth; the word telecommunication is a compound of the Greek prefix tele, meaning distant, far off, or afar, the Latin communicare, meaning to share. Its modern use is adapted from the French, because its written use was recorded in 1904 by the French engineer and novelist Édouard Estaunié. Communication was first used as an English word in the late 14th century, it comes from Old French comunicacion, from Latin communicationem, noun of action from past participle stem of communicare "to share, divide out.
Homing pigeons have been used throughout history by different cultures. Pigeon post had Persian roots, was used by the Romans to aid their military. Frontinus said; the Greeks conveyed the names of the victors at the Olympic Games to various cities using homing pigeons. In the early 19th century, the Dutch government used the system in Sumatra, and in 1849, Paul Julius Reuter started a pigeon service to fly stock prices between Aachen and Brussels, a service that operated for a year until the gap in the telegraph link was closed. In the Middle Ages, chains of beacons were used on hilltops as a means of relaying a signal. Beacon chains suffered the drawback that they could only pass a single bit of information, so the meaning of the message such as "the enemy has been sighted" had to be agreed upon in advance. One notable instance of their use was during the Spanish Armada, when a beacon chain relayed a signal from Plymouth to London. In 1792, Claude Chappe, a French engineer, built the first fixed visual telegraphy system between Lille and Paris.
However semaphore suffered from the need for skilled operators and expensive towers at intervals of ten to thirty kilometres. As a result of competition from the electrical telegraph, the last commercial line was abandoned in 1880. On 25 July 1837 the first commercial electrical telegraph was demonstrated by English inventor Sir William Fothergill Cooke, English scientist Sir Charles Wheatstone. Both inventors viewed their device as "an improvement to the electromagnetic telegraph" not as a new device. Samuel Morse independently developed a version of the electrical telegraph that he unsuccessfully demonstrated on 2 September 1837, his code was an important advance over Wheatstone's signaling method. The first transatlantic telegraph cable was completed on 27 July 1866, allowing transatlantic telecommunication for the first time; the conventional telephone was invented independently by Alexander Bell and Elisha Gray in 1876. Antonio Meucci invented the first device that allowed the electrical transmission of voice over a line in 1849.
However Meucci's device was of little practical value because it relied upon the electrophonic effect and thus required users to place the receiver in their mouth to "hear" what was being said. The first commercial telephone services were set-up in 1878 and 1879 on both sides of the Atlantic in the cities of New Haven and London. Starting in 1894, Italian inventor Guglielmo Marconi began developing a wireless communication using the newly discovered phenomenon of radio waves, showing by 1901 that they could be transmitted across the Atlantic Ocean; this was the start of wireless telegraphy by radio. Voice and music had little early success. World War I accelerated the development of radio for military communications. After the war, commercial radio AM broadcasting began in the 1920s and became an important mass medium for entertainment and news. World War II again accelerated development of radio for the wartime purposes of aircraft and land communication, radio navigation and radar. Development of stereo FM broadcasting of radio
A mineral is, broadly speaking, a solid chemical compound that occurs in pure form. A rock may consist of a single mineral, or may be an aggregate of two or more different minerals, spacially segregated into distinct phases. Compounds that occur only in living beings are excluded, but some minerals are biogenic and/or are organic compounds in the sense of chemistry. Moreover, living beings synthesize inorganic minerals that occur in rocks. In geology and mineralogy, the term "mineral" is reserved for mineral species: crystalline compounds with a well-defined chemical composition and a specific crystal structure. Minerals without a definite crystalline structure, such as opal or obsidian, are more properly called mineraloids. If a chemical compound may occur with different crystal structures, each structure is considered different mineral species. Thus, for example and stishovite are two different minerals consisting of the same compound, silicon dioxide; the International Mineralogical Association is the world's premier standard body for the definition and nomenclature of mineral species.
As of November 2018, the IMA recognizes 5,413 official mineral species. Out of more than 5,500 proposed or traditional ones; the chemical composition of a named mineral species may vary somewhat by the inclusion of small amounts of impurities. Specific varieties of a species sometimes have official names of their own. For example, amethyst is a purple variety of the mineral species quartz; some mineral species can have variable proportions of two or more chemical elements that occupy equivalent positions in the mineral's structure. Sometimes a mineral with variable composition is split into separate species, more or less arbitrarily, forming a mineral group. Besides the essential chemical composition and crystal structure, the description of a mineral species includes its common physical properties such as habit, lustre, colour, tenacity, fracture, specific gravity, fluorescence, radioactivity, as well as its taste or smell and its reaction to acid. Minerals are classified by key chemical constituents.
Silicate minerals comprise 90% of the Earth's crust. Other important mineral groups include the native elements, oxides, carbonates and phosphates. One definition of a mineral encompasses the following criteria: Formed by a natural process. Stable or metastable at room temperature. In the simplest sense, this means. Classical examples of exceptions to this rule include native mercury, which crystallizes at −39 °C, water ice, solid only below 0 °C. Modern advances have included extensive study of liquid crystals, which extensively involve mineralogy. Represented by a chemical formula. Minerals are chemical compounds, as such they can be described by fixed or a variable formula. Many mineral groups and species are composed of a solid solution. For example, the olivine group is described by the variable formula 2SiO4, a solid solution of two end-member species, magnesium-rich forsterite and iron-rich fayalite, which are described by a fixed chemical formula. Mineral species themselves could have a variable composition, such as the sulfide mackinawite, 9S8, a ferrous sulfide, but has a significant nickel impurity, reflected in its formula.
Ordered atomic arrangement. This means crystalline. An ordered atomic arrangement gives rise to a variety of macroscopic physical properties, such as crystal form and cleavage. There have been several recent proposals to classify amorphous substances as minerals; the formal definition of a mineral approved by the IMA in 1995: "A mineral is an element or chemical compound, crystalline and, formed as a result of geological processes." Abiogenic. Biogenic substances are explicitly excluded by the IMA: "Biogenic substances are chemical compounds produced by biological processes without a geological component and are not regarded as minerals. However, if geological processes were involved in the genesis of the compound the product can be accepted as a mineral."The first three general characteristics are less debated than the last two. Mineral classification schemes and their definitions are evolving to match recent advances in mineral science. Recent changes have included the addition of an organic class, in both the new Dana and the Strunz classification schemes.
The organic class includes a rare group of minerals with hydrocarbons. The IMA Commission on New Minerals and Mineral Names adopted in 2009 a hierarchical scheme for the naming and classification of mineral groups and group names and established seven commissions and four working groups to review and classify minerals into an official listing of their published names. According to these new r
Mount Everest, known in Nepali as Sagarmatha and in Tibetan as Chomolungma, is Earth's highest mountain above sea level, located in the Mahalangur Himal sub-range of the Himalayas. The international border between Nepal and China runs across its summit point; the current official elevation of 8,848 m, recognized by China and Nepal, was established by a 1955 Indian survey and subsequently confirmed by a Chinese survey in 1975. In 2005, China remeasured the rock height of the mountain, with a result of 8844.43 m. There followed an argument between China and Nepal as to whether the official height should be the rock height or the snow height. In 2010, an agreement was reached by both sides that the height of Everest is 8,848 m, Nepal recognizes China's claim that the rock height of Everest is 8,844 m. In 1865, Everest was given its official English name by the Royal Geographical Society, upon a recommendation by Andrew Waugh, the British Surveyor General of India; as there appeared to be several different local names, Waugh chose to name the mountain after his predecessor in the post, Sir George Everest, despite Everest's objections.
Mount Everest attracts many climbers, some of them experienced mountaineers. There are two main climbing routes, one approaching the summit from the southeast in Nepal and the other from the north in Tibet. While not posing substantial technical climbing challenges on the standard route, Everest presents dangers such as altitude sickness and wind, as well as significant hazards from avalanches and the Khumbu Icefall; as of 2017, nearly 300 people have died on Everest. The first recorded efforts to reach Everest's summit were made by British mountaineers; as Nepal did not allow foreigners into the country at the time, the British made several attempts on the north ridge route from the Tibetan side. After the first reconnaissance expedition by the British in 1921 reached 7,000 m on the North Col, the 1922 expedition pushed the north ridge route up to 8,320 m, marking the first time a human had climbed above 8,000 m. Seven porters were killed in an avalanche on the descent from the North Col; the 1924 expedition resulted in one of the greatest mysteries on Everest to this day: George Mallory and Andrew Irvine made a final summit attempt on 8 June but never returned, sparking debate as to whether or not they were the first to reach the top.
They had been spotted high on the mountain that day but disappeared in the clouds, never to be seen again, until Mallory's body was found in 1999 at 8,155 m on the north face. Tenzing Norgay and Edmund Hillary made the first official ascent of Everest in 1953, using the southeast ridge route. Norgay had reached 8,595 m the previous year as a member of the 1952 Swiss expedition; the Chinese mountaineering team of Wang Fuzhou, Qu Yinhua made the first reported ascent of the peak from the north ridge on 25 May 1960. The history of this area dates back to 800 BCE, when the ancient Kirati had their Kirata Kingdom in the Himalayan mountains; the Mahalangur range of the Himalaya is known as Kirat area of eastern Nepal. In 1715, the Qing Empire of China surveyed the mountain while mapping its territory and depicted it as Mount Qomolangma no than 1719. In 1802, the British began the Great Trigonometric Survey of India to fix the locations and names of the world's highest mountains. Starting in southern India, the survey teams moved northward using giant theodolites, each weighing 500 kg and requiring 12 men to carry, to measure heights as as possible.
They reached the Himalayan foothills by the 1830s, but Nepal was unwilling to allow the British to enter the country due to suspicions of political aggression and possible annexation. Several requests by the surveyors to enter Nepal were turned down; the British were forced to continue their observations from Terai, a region south of Nepal, parallel to the Himalayas. Conditions in Terai were difficult because of malaria. Three survey officers died from malaria. Nonetheless, in 1847, the British continued the survey and began detailed observations of the Himalayan peaks from observation stations up to 240 km distant. Weather restricted work to the last three months of the year. In November 1847, Andrew Waugh, the British Surveyor General of India made several observations from the Sawajpore station at the east end of the Himalayas. Kangchenjunga was considered the highest peak in the world, with interest, he noted a peak beyond it, about 230 km away. John Armstrong, one of Waugh's subordinates saw the peak from a site farther west and called it peak "b".
Waugh would write that the observations indicated that peak "b" was higher than Kangchenjunga, but given the great distance of the observations, closer observations were required for verification. The following year, Waugh sent a survey official back to Terai to make closer observations of peak "b", but clouds thwarted his attempts. In 1849, Waugh dispatched James Nicolson to the area, who made two observations from Jirol, 190 km away. Nicolson took the largest theodolite and headed east, obtaining over 30 observations from five different locations, with the closest being 174 km from the peak. Nicolson retreated to Patna on the Ganges to perform the necessary calculations based on his observations, his raw data gave an average height of 9,200 m for peak "b", but this did not consider light refraction, which distorts heights. However, the number indica