The Eiffel Tower is a wrought-iron lattice tower on the Champ de Mars in Paris, France. It is built the tower. Constructed from 1887 to 1889 as the entrance to the 1889 World's Fair, it was criticised by some of France's leading artists and intellectuals for its design, but it has become a global cultural icon of France and one of the most recognisable structures in the world; the Eiffel Tower is the most-visited paid monument in the world. The tower is 324 metres tall, about the same height as an 81-storey building, the tallest structure in Paris, its base is square. During its construction, the Eiffel Tower surpassed the Washington Monument to become the tallest man-made structure in the world, a title it held for 41 years until the Chrysler Building in New York City was finished in 1930. Due to the addition of a broadcasting aerial at the top of the tower in 1957, it is now taller than the Chrysler Building by 5.2 metres. Excluding transmitters, the Eiffel Tower is the second tallest free-standing structure in France after the Millau Viaduct.
The tower has three levels for visitors, with restaurants on the second levels. The top level's upper platform is 276 m above the ground – the highest observation deck accessible to the public in the European Union. Tickets can be purchased to lift to the first and second levels; the climb from ground level to the first level is over 300 steps, as is the climb from the first level to the second. Although there is a staircase to the top level, it is accessible only by lift; the design of the Eiffel Tower is attributed to Maurice Koechlin and Émile Nouguier, two senior engineers working for the Compagnie des Établissements Eiffel. It was envisioned after discussion about a suitable centrepiece for the proposed 1889 Exposition Universelle, a world's fair to celebrate the centennial of the French Revolution. Eiffel acknowledged that inspiration for a tower came from the Latting Observatory built in New York City in 1853. In May 1884, working at home, Koechlin made a sketch of their idea, described by him as "a great pylon, consisting of four lattice girders standing apart at the base and coming together at the top, joined together by metal trusses at regular intervals".
Eiffel showed little enthusiasm, but he did approve further study, the two engineers asked Stephen Sauvestre, the head of company's architectural department, to contribute to the design. Sauvestre added decorative arches to the base of the tower, a glass pavilion to the first level, other embellishments; the new version gained Eiffel's support: he bought the rights to the patent on the design which Koechlin and Sauvestre had taken out, the design was exhibited at the Exhibition of Decorative Arts in the autumn of 1884 under the company name. On 30 March 1885, Eiffel presented his plans to the Société des Ingénieurs Civils. Little progress was made until 1886, when Jules Grévy was re-elected as president of France and Édouard Lockroy was appointed as minister for trade. A budget for the exposition was passed and, on 1 May, Lockroy announced an alteration to the terms of the open competition being held for a centrepiece to the exposition, which made the selection of Eiffel's design a foregone conclusion, as entries had to include a study for a 300 m four-sided metal tower on the Champ de Mars..
On 12 May, a commission was set up to examine Eiffel's scheme and its rivals, which, a month decided that all the proposals except Eiffel's were either impractical or lacking in details. After some debate about the exact location of the tower, a contract was signed on 8 January 1887; this was signed by Eiffel acting in his own capacity rather than as the representative of his company, granted him 1.5 million francs toward the construction costs: less than a quarter of the estimated 6.5 million francs. Eiffel was to receive all income from the commercial exploitation of the tower during the exhibition and for the next 20 years, he established a separate company to manage the tower, putting up half the necessary capital himself. The proposed tower had been a subject of controversy, drawing criticism from those who did not believe it was feasible and those who objected on artistic grounds; these objections were an expression of a long-standing debate in France about the relationship between architecture and engineering.
It came to a head as work began at the Champ de Mars: a "Committee of Three Hundred" was formed, led by the prominent architect Charles Garnier and including some of the most important figures of the arts, such as Adolphe Bouguereau, Guy de Maupassant, Charles Gounod and Jules Massenet. A petition called "Artists against the Eiffel Tower" was sent to the Minister of Works and Commissioner for the Exposition, Charles Alphand, it was published by Le Temps on 14 February 1887: We, painters, sculptors and passionate devotees of the hitherto untouched beauty of Paris, protest with all our strength, with all our indignation in the name
Extraterrestrial life called alien life, is life that occurs outside of Earth and that did not originate from Earth. These hypothetical life forms may range from simple prokaryotes to beings with civilizations far more advanced than humanity; the Drake equation speculates about the existence of intelligent life elsewhere in the universe. The science of extraterrestrial life in all its forms is known as exobiology. Since the mid-20th century, there has been an ongoing search for signs of extraterrestrial life; this encompasses a search for current and historic extraterrestrial life, a narrower search for extraterrestrial intelligent life. Depending on the category of search, methods range from the analysis of telescope and specimen data to radios used to detect and send communication signals; the concept of extraterrestrial life, extraterrestrial intelligence, has had a major cultural impact, chiefly in works of science fiction. Over the years, science fiction communicated scientific ideas, imagined a wide range of possibilities, influenced public interest in and perspectives of extraterrestrial life.
One shared space is the debate over the wisdom of attempting communication with extraterrestrial intelligence. Some encourage aggressive methods to try for contact with intelligent extraterrestrial life. Others—citing the tendency of technologically advanced human societies to enslave or wipe out less advanced societies—argue that it may be dangerous to call attention to Earth. Alien life, such as microorganisms, has been hypothesized to exist in the Solar System and throughout the universe; this hypothesis relies on consistent physical laws of the observable universe. According to this argument, made by scientists such as Carl Sagan and Stephen Hawking, as well as well-regarded thinkers such as Winston Churchill, it would be improbable for life not to exist somewhere other than Earth; this argument is embodied in the Copernican principle, which states that Earth does not occupy a unique position in the Universe, the mediocrity principle, which states that there is nothing special about life on Earth.
The chemistry of life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the universe was only 10–17 million years old. Life may have emerged independently at many places throughout the universe. Alternatively, life may have formed less then spread—by meteoroids, for example—between habitable planets in a process called panspermia. In any case, complex organic molecules may have formed in the protoplanetary disk of dust grains surrounding the Sun before the formation of Earth. According to these studies, this process may occur outside Earth on several planets and moons of the Solar System and on planets of other stars. Since the 1950s, scientists have proposed that "habitable zones" around stars are the most places to find life. Numerous discoveries in such zones since 2007 have generated numerical estimates of Earth-like planets —in terms of composition—of many billions; as of 2013, only a few planets have been discovered in these zones. Nonetheless, on 4 November 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarfs in the Milky Way, 11 billion of which may be orbiting Sun-like stars.
The nearest such planet may be 12 light-years away, according to the scientists. Astrobiologists have considered a "follow the energy" view of potential habitats. A study published in 2017 suggests that due to how complexity evolved in species on Earth, the level of predictability for alien evolution elsewhere would make them look similar to life on our planet. One of the study authors, Sam Levin, notes "Like humans, we predict that they are made-up of a hierarchy of entities, which all cooperate to produce an alien. At each level of the organism there will be mechanisms in place to eliminate conflict, maintain cooperation, keep the organism functioning. We can offer some examples of what these mechanisms will be." There is research in assessing the capacity of life for developing intelligence. It has been suggested that this capacity arises with the number of potential niches a planet contains, that the complexity of life itself is reflected in the information density of planetary environments, which in turn can be computed from its niches.
Biologist David Zeigler has argued that, based on evolutionary convergence from many different ancestral groups on Earth, a worm form is a life form on other life-bearing planets. Life on Earth requires water as a solvent in place. Sufficient quantities of carbon and other elements, along with water, might enable the formation of living organisms on terrestrial planets with a chemical make-up and temperature range similar to that of Earth. More life based on ammonia has been suggested, though this solvent appears less suitable than water, it is conceivable that there are forms of life whose solvent is a liquid hydrocarbon, such as methane, ethane or propane. About 29 chemical elements play an active positive role in living organisms on Earth. About 95% of living matter is built upon only six elements: carbon, nitrogen, oxygen and sulfur; these six elements form the basic building blocks of all life on Earth, whereas most of the remaining elements are found only in trace amounts. The unique characteristics of carbon make it unlikely that it could be replaced on another planet, to generate the biochemistry necessary for life.
The carbon atom has the unique ability to make four strong chemical
Intelligence has been defined in many ways, including: the capacity for logic, self-awareness, emotional knowledge, planning, critical thinking, problem solving. More it can be described as the ability to perceive or infer information, to retain it as knowledge to be applied towards adaptive behaviors within an environment or context. Intelligence is most studied in humans but has been observed in both non-human animals and in plants. Intelligence in machines is called artificial intelligence, implemented in computer systems using programs and, appropriate hardware; the word "intelligence" derives from the Latin nouns intelligentia or intellēctus, which in turn stem from the verb intelligere, to comprehend or perceive. In the Middle Ages, the word intellectus became the scholarly technical term for understanding, a translation for the Greek philosophical term nous; this term, was linked to the metaphysical and cosmological theories of teleological scholasticism, including theories of the immortality of the soul, the concept of the Active Intellect.
This entire approach to the study of nature was rejected by the early modern philosophers such as Francis Bacon, Thomas Hobbes, John Locke, David Hume, all of whom preferred the word "understanding" in their English philosophical works. Hobbes for example, in his Latin De Corpore, used "intellectus intelligit", translated in the English version as "the understanding understandeth", as a typical example of a logical absurdity; the term "intelligence" has therefore become less common in English language philosophy, but it has been taken up in more contemporary psychology. The definition of intelligence is controversial; some groups of psychologists have suggested the following definitions: From "Mainstream Science on Intelligence", an op-ed statement in the Wall Street Journal signed by fifty-two researchers: A general mental capability that, among other things, involves the ability to reason, solve problems, think abstractly, comprehend complex ideas and learn from experience. It is not book learning, a narrow academic skill, or test-taking smarts.
Rather, it reflects a broader and deeper capability for comprehending our surroundings—"catching on," "making sense" of things, or "figuring out" what to do. From Intelligence: Knowns and Unknowns, a report published by the Board of Scientific Affairs of the American Psychological Association: Individuals differ from one another in their ability to understand complex ideas, to adapt to the environment, to learn from experience, to engage in various forms of reasoning, to overcome obstacles by taking thought. Although these individual differences can be substantial, they are never consistent: a given person's intellectual performance will vary on different occasions, in different domains, as judged by different criteria. Concepts of "intelligence" are attempts to organize this complex set of phenomena. Although considerable clarity has been achieved in some areas, no such conceptualization has yet answered all the important questions, none commands universal assent. Indeed, when two dozen prominent theorists were asked to define intelligence, they gave two dozen, somewhat different, definitions.
Besides those definitions and learning researchers have suggested definitions of intelligence such as: Human intelligence is the intellectual power of humans, marked by complex cognitive feats and high levels of motivation and self-awareness. Intelligence enables humans to remember descriptions of things and use those descriptions in future behaviors, it is a cognitive process. It gives humans the cognitive abilities to learn, form concepts and reason, including the capacities to recognize patterns, comprehend ideas, solve problems, use language to communicate. Intelligence enables humans to think. Note that much of the above definition applies to the intelligence of non-human animals. Although humans have been the primary focus of intelligence researchers, scientists have attempted to investigate animal intelligence, or more broadly, animal cognition; these researchers are interested in studying both mental ability in a particular species, comparing abilities between species. They study various measures of problem solving, as well as verbal reasoning abilities.
Some challenges in this area are defining intelligence so that it has the same meaning across species, operationalizing a measure that compares mental ability across different species and contexts. Wolfgang Köhler's research on the intelligence of apes is an example of research in this area. Stanley Coren's book, The Intelligence of Dogs is a notable book on the topic of dog intelligence. Non-human animals noted and studied for their intelligence include chimpanzees and other great apes, elephants and to some extent parrots and ravens. Cephalopod intelligence provides important comparative study. Cephalopods appear to exhibit characteristics of significant intelligence, yet their nervous systems differ radically from those of backboned animals. Vertebrates such as mammals, birds and fish have shown a high degree of intellect that varies according to each species; the same is true with arthropods. Evidence of a general factor of intell
South America is a continent in the Western Hemisphere in the Southern Hemisphere, with a small portion in the Northern Hemisphere. It may be considered a subcontinent of the Americas, how it is viewed in the Spanish and Portuguese-speaking regions of the Americas; the reference to South America instead of other regions has increased in the last decades due to changing geopolitical dynamics. It is bordered on the west on the north and east by the Atlantic Ocean, it includes twelve sovereign states, a part of France, a non-sovereign area. In addition to this, the ABC islands of the Kingdom of the Netherlands and Tobago, Panama may be considered part of South America. South America has an area of 17,840,000 square kilometers, its population as of 2016 has been estimated at more than 420 million. South America ranks fourth in fifth in population. Brazil is by far the most populous South American country, with more than half of the continent's population, followed by Colombia, Argentina and Peru. In recent decades Brazil has concentrated half of the region's GDP and has become a first regional power.
Most of the population lives near the continent's western or eastern coasts while the interior and the far south are sparsely populated. The geography of western South America is dominated by the Andes mountains. Most of the continent lies in the tropics; the continent's cultural and ethnic outlook has its origin with the interaction of indigenous peoples with European conquerors and immigrants and, more locally, with African slaves. Given a long history of colonialism, the overwhelming majority of South Americans speak Portuguese or Spanish, societies and states reflect Western traditions. South America occupies the southern portion of the Americas; the continent is delimited on the northwest by the Darién watershed along the Colombia–Panama border, although some may consider the border instead to be the Panama Canal. Geopolitically and geographically all of Panama – including the segment east of the Panama Canal in the isthmus – is included in North America alone and among the countries of Central America.
All of mainland South America sits on the South American Plate. South America is home to Angel Falls in Venezuela. South America's major mineral resources are gold, copper, iron ore and petroleum; these resources found in South America have brought high income to its countries in times of war or of rapid economic growth by industrialized countries elsewhere. However, the concentration in producing one major export commodity has hindered the development of diversified economies; the fluctuation in the price of commodities in the international markets has led to major highs and lows in the economies of South American states causing extreme political instability. This is leading to efforts to diversify production to drive away from staying as economies dedicated to one major export. South America is one of the most biodiverse continents on earth. South America is home to many interesting and unique species of animals including the llama, piranha, vicuña, tapir; the Amazon rainforests possess high biodiversity, containing a major proportion of the Earth's species.
Brazil is the largest country in South America, encompassing around half of the continent's land area and population. The remaining countries and territories are divided among three regions: The Andean States, the Guianas and the Southern Cone. Traditionally, South America includes some of the nearby islands. Aruba, Curaçao, Trinidad and the federal dependencies of Venezuela sit on the northerly South American continental shelf and are considered part of the continent. Geo-politically, the island states and overseas territories of the Caribbean are grouped as a part or subregion of North America, since they are more distant on the Caribbean Plate though San Andres and Providencia are politically part of Colombia and Aves Island is controlled by Venezuela. Other islands that are included with South America are the Galápagos Islands that belong to Ecuador and Easter Island, Robinson Crusoe Island, Chiloé and Tierra del Fuego. In the Atlantic, Brazil owns Fernando de Noronha and Martim Vaz, the Saint Peter and Saint Paul Archipelago, while the Falkland Islands are governed by the United Kingdom, whose sovereignty over the islands is disputed by Argentina.
South Georgia and the South Sandwich Islands may be associate
India known as the Republic of India, is a country in South Asia. It is the seventh largest country by area and with more than 1.3 billion people, it is the second most populous country as well as the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the southwest, the Bay of Bengal on the southeast, it shares land borders with Pakistan to the west. In the Indian Ocean, India is in the vicinity of Sri Lanka and the Maldives, while its Andaman and Nicobar Islands share a maritime border with Thailand and Indonesia; the Indian subcontinent was home to the urban Indus Valley Civilisation of the 3rd millennium BCE. In the following millennium, the oldest scriptures associated with Hinduism began to be composed. Social stratification, based on caste, emerged in the first millennium BCE, Buddhism and Jainism arose. Early political consolidations took place under the Gupta empires. In the medieval era, Zoroastrianism and Islam arrived, Sikhism emerged, all adding to the region's diverse culture.
Much of the north fell to the Delhi Sultanate. The economy expanded in the 17th century in the Mughal Empire. In the mid-18th century, the subcontinent came under British East India Company rule, in the mid-19th under British Crown rule. A nationalist movement emerged in the late 19th century, which under Mahatma Gandhi, was noted for nonviolent resistance and led to India's independence in 1947. In 2017, the Indian economy was the world's sixth largest by nominal GDP and third largest by purchasing power parity. Following market-based economic reforms in 1991, India became one of the fastest-growing major economies and is considered a newly industrialised country. However, it continues to face the challenges of poverty, corruption and inadequate public healthcare. A nuclear weapons state and regional power, it has the second largest standing army in the world and ranks fifth in military expenditure among nations. India is a federal republic governed under a parliamentary system and consists of 29 states and 7 union territories.
A pluralistic and multi-ethnic society, it is home to a diversity of wildlife in a variety of protected habitats. The name India is derived from Indus, which originates from the Old Persian word Hindush, equivalent to the Sanskrit word Sindhu, the historical local appellation for the Indus River; the ancient Greeks referred to the Indians as Indoi, which translates as "The people of the Indus". The geographical term Bharat, recognised by the Constitution of India as an official name for the country, is used by many Indian languages in its variations, it is a modernisation of the historical name Bharatavarsha, which traditionally referred to the Indian subcontinent and gained increasing currency from the mid-19th century as a native name for India. Hindustan is a Middle Persian name for India, it was introduced into India by the Mughals and used since then. Its meaning varied, referring to a region that encompassed northern India and Pakistan or India in its entirety; the name may refer to either the northern part of India or the entire country.
The earliest known human remains in South Asia date to about 30,000 years ago. Nearly contemporaneous human rock art sites have been found in many parts of the Indian subcontinent, including at the Bhimbetka rock shelters in Madhya Pradesh. After 6500 BCE, evidence for domestication of food crops and animals, construction of permanent structures, storage of agricultural surplus, appeared in Mehrgarh and other sites in what is now Balochistan; these developed into the Indus Valley Civilisation, the first urban culture in South Asia, which flourished during 2500–1900 BCE in what is now Pakistan and western India. Centred around cities such as Mohenjo-daro, Harappa and Kalibangan, relying on varied forms of subsistence, the civilization engaged robustly in crafts production and wide-ranging trade. During the period 2000–500 BCE, many regions of the subcontinent transitioned from the Chalcolithic cultures to the Iron Age ones; the Vedas, the oldest scriptures associated with Hinduism, were composed during this period, historians have analysed these to posit a Vedic culture in the Punjab region and the upper Gangetic Plain.
Most historians consider this period to have encompassed several waves of Indo-Aryan migration into the subcontinent from the north-west. The caste system, which created a hierarchy of priests and free peasants, but which excluded indigenous peoples by labeling their occupations impure, arose during this period. On the Deccan Plateau, archaeological evidence from this period suggests the existence of a chiefdom stage of political organisation. In South India, a progression to sedentary life is indicated by the large number of megalithic monuments dating from this period, as well as by nearby traces of agriculture, irrigation tanks, craft traditions. In the late Vedic period, around the 6th century BCE, the small states and chiefdoms of the Ganges Plain and the north-western regions had consolidated into 16 major oligarchies and monarchies that were known as the mahajanapadas; the emerging urbanisation gave rise to non-Vedic religious movements, two of which became independent religions. Jainism came into prominence during the life of Mahavira.
Buddhism, based on the teachings of Gautama Buddha, attracted followers from all social classes excepting the middle
Bengali science fiction
Bengali science fiction is a part of Bengali literature containing science fiction elements. Science fiction in the Bengali language is known as "kalpabigyan". Bengali writers wrote various science fiction works in the 19th and early 20th centuries during the British Raj, before the partition of India. Isaac Asimov’s assertion that "true science fiction could not exist until people understood the rationalism of science and began to use it with respect in their stories" is true for the earliest science fiction written in the Bengali language; the earliest notable Bengali science fiction was Jagadananda Roy's Shukra Bhraman. This story is of particular interest to literary historians, as it described a journey to another planet, their bodies were covered with dense black fur. Their heads were larger in comparison with their bodies, limbs sported long nails and they were naked." This story was published a decade before H. G. Wells’s The War of the Worlds in which Wells describes the aliens from Mars.
Some specialists credit Hemlal Dutta as one of the earliest Bengali science fiction writers for his Rohosso. This story was published in two installments in 1882 in the pictorial magazine Bigyan Dorpon. In 1896, Jagadish Chandra Bose, considered to be the father of Bengali science fiction, wrote Niruddesher Kahini; this tale of weather control, one of the first Bengali science fiction works, features getting rid of a cyclone using a little bottle of hair oil. He included the story with changes in the collection of essays titled Abyakto as Palatak Tufan. Both versions of the story have been translated into English by Bodhisattva Chattopadhyay. Roquia Sakhawat Hussain, an early Islamic feminist, wrote Sultana's Dream, one of the earliest examples of feminist science fiction in any language, it depicts a feminist utopia of role reversal, in which men are locked away in seclusion, in a manner corresponding to the traditional Muslim practice of purdah for women. The short story, written in English, was first published in the Madras-based Indian Ladies Magazine in 1905, three years appeared as a book.
Premendra Mitra wrote Kuhoker Deshe. Hemendra Kumar Ray wrote Meghduter Morte Agomon. After Qazi Abdul Halim's Mohasunner Kanna was the first modern East Bengali science fiction novel. After independence Humayun Ahmed wrote Tomader Jonno Valobasa, it was published in 1973. This book is treated as the first full-fledged Bangladeshi science fiction novel, he wrote Tara Tinjon, Anonto Nakshatra Bithi, Fiha Somikoron, other works. Bengali science fiction is considered to have reached a new level of literary sophistication with the contributions of Muhammed Zafar Iqbal. Iqbal wrote; this story was included in a compilation of Iqbal's work in a book by the same name. Muktodhara, a famous publishing house of Dhaka was the publisher of this book; this collection of science fiction stories gained huge popularity and the new trend of science fiction emerged among Bengali writers and readers. After his first collection, Mr. Iqbal transformed his own science fiction cartoon strip Mohakashe Mohatrash into a novel.
All told, Muhammed Zafar Iqbal has written the greatest number of science fiction works in Bengali science fiction. Following in the footsteps of the ancestors and more writers young writers, started writing science fiction, a new era of writing started in the writing of Bengali literature. In 1997, the first and longest-running Bangladeshi science fiction magazine, was first published, with famous cartoonist Ahsan Habib as the editor; this monthly magazine played an important role in the development of Bengali science fiction in Bangladesh. A number of new and promising science fiction writers including Rabiul Hasan Avi, Anik Khan, Asrar Masud, Sajjad Kabir, Russel Ahmed, Mizanur Rahman Kallol came of age while working with the magazine. Nasim Sahnic is a promising young science fiction writer in Bangladesh, his latest science fiction books like Genetic code, Sundarbone Truti, Coxsbazarer Cossop are famous to young generation. Other notable writers in the genre include: Vobdesh Ray, Rakib Hasan, Nipun Alam, Ali Imam, Qazi Anwar Hussain,Altamas Pasha, Abdul Ahad, Anirudha Alam, Ahsanul Habib, Kamal Arsalan, Dr. Ahmed Mujibar Rahman, Moinul Ahsan Saber, Swapan Kumar Gayen, Mohammad Zaidul Alam, Mostafa Tanim, Muhammad Anwarul Hoque Khan, Jubaida Gulshan Ara Hena, Amirul Islam, Touhidur Rahman, Zakaria Swapan and Qazi Shahnur Hussain.
Mr. Khan loves to write science fiction on parallel mystery of science or mathematics. A number of writers from West Bengal, India have written science fiction. Credit for the first Bengali science fiction story is given to Bengali authors such as Jagadananda Roy, Hemlal Dutta and the polymath Jagadish Chandra Bose. Eminent film maker and writer Satyajit Ray enriched Bengali science fiction by writing many short stories as well as science fiction series, Professor Shonku. Professor Shonku is a fictional scientist created by Satyajit Ray in a series of Bengali science fiction books, his full name is Trilokeshwar Shonku, by occupation, he is an inventor. A short story known as The Alien written by Satyajit Ray about an alien named "Mr. Ang" gained pop
Hinduism is an Indian religion and dharma, or way of life practised in the Indian subcontinent and parts of Southeast Asia. Hinduism has been called the oldest religion in the world, some practitioners and scholars refer to it as Sanātana Dharma, "the eternal tradition", or the "eternal way", beyond human history. Scholars regard Hinduism as a fusion or synthesis of various Indian cultures and traditions, with diverse roots and no founder; this "Hindu synthesis" started to develop between 500 BCE and 300 CE, after the end of the Vedic period, flourished in the medieval period, with the decline of Buddhism in India. Although Hinduism contains a broad range of philosophies, it is linked by shared concepts, recognisable rituals, shared textual resources, pilgrimage to sacred sites. Hindu texts are classified into Smṛti; these texts discuss theology, mythology, Vedic yajna, agamic rituals, temple building, among other topics. Major scriptures include the Vedas and Upanishads, the Bhagavad Gita, the Ramayana, the Āgamas.
Sources of authority and eternal truths in its texts play an important role, but there is a strong Hindu tradition of questioning authority in order to deepen the understanding of these truths and to further develop the tradition. Prominent themes in Hindu beliefs include the four Puruṣārthas, the proper goals or aims of human life, namely Dharma, Artha and Moksha. Hindu practices include rituals such as puja and recitations, meditation, family-oriented rites of passage, annual festivals, occasional pilgrimages; some Hindus leave their social world and material possessions engage in lifelong Sannyasa to achieve Moksha. Hinduism prescribes the eternal duties, such as honesty, refraining from injuring living beings, forbearance, self-restraint, compassion, among others; the four largest denominations of Hinduism are the Vaishnavism, Shaivism and Smartism. Hinduism is the world's third largest religion. Hinduism is the most professed faith in India and Mauritius, it is the predominant religion in Bali, Indonesia.
Significant numbers of Hindu communities are found in the Caribbean, North America, other countries. The word Hindū is derived from Indo-Aryan/Sanskrit root Sindhu; the Proto-Iranian sound change *s > h occurred between 850–600 BCE, according to Asko Parpola. It is believed that Hindu was used as the name for the Indus River in the northwestern part of the Indian subcontinent. According to Gavin Flood, "The actual term Hindu first occurs as a Persian geographical term for the people who lived beyond the river Indus", more in the 6th-century BCE inscription of Darius I; the term Hindu in these ancient records did not refer to a religion. Among the earliest known records of'Hindu' with connotations of religion may be in the 7th-century CE Chinese text Record of the Western Regions by Xuanzang, 14th-century Persian text Futuhu's-salatin by'Abd al-Malik Isami. Thapar states that the word Hindu is found as heptahindu in Avesta – equivalent to Rigvedic sapta sindhu, while hndstn is found in a Sasanian inscription from the 3rd century CE, both of which refer to parts of northwestern South Asia.
The Arabic term al-Hind referred to the people. This Arabic term was itself taken from the pre-Islamic Persian term Hindū, which refers to all Indians. By the 13th century, Hindustan emerged as a popular alternative name of India, meaning the "land of Hindus"; the term Hindu was used in some Sanskrit texts such as the Rajataranginis of Kashmir and some 16th- to 18th-century Bengali Gaudiya Vaishnava texts including Chaitanya Charitamrita and Chaitanya Bhagavata. These texts used it to distinguish Hindus from Muslims who are called Yavanas or Mlecchas, with the 16th-century Chaitanya Charitamrita text and the 17th-century Bhakta Mala text using the phrase "Hindu dharma", it was only towards the end of the 18th century that European merchants and colonists began to refer to the followers of Indian religions collectively as Hindus. The term Hinduism spelled Hindooism, was introduced into the English language in the 18th century to denote the religious and cultural traditions native to India. Hinduism includes a diversity of ideas on spirituality and traditions, but has no ecclesiastical order, no unquestionable religious authorities, no governing body, no prophet nor any binding holy book.
Because of the wide range of traditions and ideas covered by the term Hinduism, arriving at a comprehensive definition is difficult. The religion "defies our desire to define and categorize it". Hinduism has been variously defined as a religion, a religious tradition, a set of religious beliefs, "a way of life". From a Western lexical standpoint, Hinduism like other faiths is appropriately referred to as a religion. In India the term dharma is preferred, broader than the Western term religion; the study of India and its cultures and religions, the definition of "Hinduism", has been shaped by th