Children's literature or juvenile literature includes stories, books and poems that are enjoyed by children. Modern children's literature is classified in two different ways: genre or the intended age of the reader. Children's literature can be traced to stories and songs, part of a wider oral tradition, that adults shared with children before publishing existed; the development of early children's literature, before printing was invented, is difficult to trace. After printing became widespread, many classic "children's" tales were created for adults and adapted for a younger audience. Since the fifteenth century much literature has been aimed at children with a moral or religious message; the late nineteenth and early twentieth centuries is known as the "Golden Age of Children's Literature", because many classic children's books were published then. There is no single or used definition of children's literature, it can be broadly defined as anything that children read or more defined as fiction, non-fiction, poetry, or drama intended for and used by children and young people.
One writer on children's literature defines it as "all books written for children, excluding works such as comic books, joke books, cartoon books, non-fiction works that are not intended to be read from front to back, such as dictionaries and other reference materials". However, others would argue that comics should be included: "Children's Literature studies has traditionally treated comics fitfully and superficially despite the importance of comics as a global phenomenon associated with children"; the International Companion Encyclopedia of Children's Literature notes that "the boundaries of genre... are not fixed but blurred". Sometimes, no agreement can be reached about whether a given work is best categorized as literature for adults or children; some works defy easy categorization. J. K. Rowling's Harry Potter series was written and marketed for young adults, but it is popular among adults; the series' extreme popularity led The New York Times to create a separate best-seller list for children's books.
Despite the widespread association of children's literature with picture books, spoken narratives existed before printing, the root of many children's tales go back to ancient storytellers. Seth Lerer, in the opening of Children's Literature: A Reader's History from Aesop to Harry Potter, says, "This book presents a history of what children have heard and read... The history I write of is a history of reception." Early children's literature consisted of spoken stories and poems that were used to educate and entertain children. It was only in the eighteenth century, with the development of the concept of childhood, that a separate genre of children's literature began to emerge, with its own divisions and canon; the earliest of these books were educational books, books on conduct, simple ABCs—often decorated with animals and anthropomorphic letters. In 1962, French historian Philippe Ariès argues in his book Centuries of Childhood that the modern concept of childhood only emerged in recent times.
He explains that children were in the past not considered as different from adults and were not given different treatment. As evidence for this position, he notes that, apart from instructional and didactic texts for children written by clerics like the Venerable Bede and Ælfric of Eynsham, there was a lack of any genuine literature aimed at children before the 18th century. Other scholars have qualified this viewpoint by noting that there was a literature designed to convey the values and information necessary for children within their cultures, such as the Play of Daniel from the 12th century. Pre-modern children's literature, tended to be of a didactic and moralistic nature, with the purpose of conveying conduct-related and religious lessons. During the 17th century, the concept of childhood began to emerge in Europe. Adults saw children as separate beings, innocent and in need of protection and training by the adults around them; the English philosopher John Locke developed his theory of the tabula rasa in his 1690 An Essay Concerning Human Understanding.
In Locke's philosophy, tabula rasa was the theory that the mind is at birth a "blank slate" without rules for processing data, that data is added and rules for processing are formed by one's sensory experiences. A corollary of this doctrine was that the mind of the child was born blank and that it was the duty of the parents to imbue the child with correct notions. Locke himself emphasized the importance of providing children with "easy pleasant books" to develop their minds rather than using force to compel them, he suggested that picture books be created for children. In the nineteenth century, a few children's titles became famous as classroom reading texts. Among these were the fables of Aesop and Jean de la Fontaine and Charles Perraults's 1697 Tales of Mother Goose; the popularity of these texts led to the creation of a number of nineteenth-century fantasy and fairy tales for children which featured magic objects and talking animals. Another influence on this shift in attitudes came from Puritanism, which stressed the importance of individual salvation.
Puritans were concerned with the spiritual welfare of their children, there was a large growth in the publication of "good godly books" aimed squarely at children. Some of the most popular works were by James Janeway, but the most enduring book from this movement, still read toda
The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
Massachusetts the Commonwealth of Massachusetts, is the most populous state in the New England region of the northeastern United States. It borders on the Atlantic Ocean to the east, the states of Connecticut and Rhode Island to the south, New Hampshire and Vermont to the north, New York to the west; the state is named after the Massachusett tribe, which once inhabited the east side of the area, is one of the original thirteen states. The capital of Massachusetts is Boston, the most populous city in New England. Over 80% of Massachusetts's population lives in the Greater Boston metropolitan area, a region influential upon American history and industry. Dependent on agriculture and trade, Massachusetts was transformed into a manufacturing center during the Industrial Revolution. During the 20th century, Massachusetts's economy shifted from manufacturing to services. Modern Massachusetts is a global leader in biotechnology, higher education and maritime trade. Plymouth was the site of the second colony in New England after Popham Colony in 1607 in what is now Maine.
Plymouth was founded in 1620 by passengers of the Mayflower. In 1692, the town of Salem and surrounding areas experienced one of America's most infamous cases of mass hysteria, the Salem witch trials. In 1777, General Henry Knox founded the Springfield Armory, which during the Industrial Revolution catalyzed numerous important technological advances, including interchangeable parts. In 1786, Shays' Rebellion, a populist revolt led by disaffected American Revolutionary War veterans, influenced the United States Constitutional Convention. In the 18th century, the Protestant First Great Awakening, which swept the Atlantic World, originated from the pulpit of Northampton preacher Jonathan Edwards. In the late 18th century, Boston became known as the "Cradle of Liberty" for the agitation there that led to the American Revolution; the entire Commonwealth of Massachusetts has played a powerful commercial and cultural role in the history of the United States. Before the American Civil War, Massachusetts was a center for the abolitionist and transcendentalist movements.
In the late 19th century, the sports of basketball and volleyball were invented in the western Massachusetts cities of Springfield and Holyoke, respectively. In 2004, Massachusetts became the first U. S. state to recognize same-sex marriage as a result of the decision in Goodridge v. Department of Public Health by the Massachusetts Supreme Judicial Court. Many prominent American political dynasties have hailed from the state, including the Adams and Kennedy families. Harvard University in Cambridge is the oldest institution of higher learning in the United States, with the largest financial endowment of any university, Harvard Law School has educated a contemporaneous majority of Justices of the Supreme Court of the United States. Kendall Square in Cambridge has been called "the most innovative square mile on the planet", in reference to the high concentration of entrepreneurial start-ups and quality of innovation which have emerged in the vicinity of the square since 2010. Both Harvard University and the Massachusetts Institute of Technology in Cambridge, have been ranked among the most regarded academic institutions in the world.
Massachusetts' public-school students place among the top tier in the world in academic performance, the state has been ranked as one of the top states in the United States for citizens to live in, as well as one of the most expensive. The Massachusetts Bay Colony was named after the indigenous population, the Massachusett derived from a Wôpanâak word muswach8sut, segmented as mus "big" + wach8 "mountain" + -s "diminutive" + -ut "locative", it has been translated as "near the great hill", "by the blue hills", "at the little big hill", or "at the range of hills", referring to the Blue Hills, or in particular the Great Blue Hill, located on the boundary of Milton and Canton. Alternatively, Massachusett has been represented as Moswetuset—from the name of the Moswetuset Hummock in Quincy, where Plymouth Colony commander Myles Standish, hired English military officer, Squanto, part of the now disappeared Patuxet band of the Wampanoag peoples, met Chief Chickatawbut in 1621; the official name of the state is the "Commonwealth of Massachusetts".
While this designation is part of the state's official name, it has no practical implications. Massachusetts has powers within the United States as other states, it may have been chosen by John Adams for the second draft of the Massachusetts Constitution because unlike the word "state", "commonwealth" at the time had the connotation of a republic, in contrast to the monarchy the former American colonies were fighting against. Massachusetts was inhabited by tribes of the Algonquian language family such as the Wampanoag, Nipmuc, Pocomtuc and Massachusett. While cultivation of crops like squash and corn supplemented their diets, these tribes were dependent on hunting and fishing for most of their food. Villages consisted of lodges called wigwams as well as longhouses, tribes were led by male or female elders known as sachems. In the early 1600s, after contact had been made with Europeans, large numbers of the indigenous peoples in the northeast of what is now the United States were killed by virgin soil epidemics such as smallpox, measles and leptospirosis.
Between 1617 and 1619, smallpox killed ap
Moses was a prophet according to the teachings of the Abrahamic religions. Scholarly consensus sees Moses as a legendary figure. According to the Hebrew Bible, he was adopted by an Egyptian princess, in life became the leader of the Israelites and lawgiver, to whom the authorship of the Torah, or acquisition of the Torah from Heaven is traditionally attributed. Called Moshe Rabbenu in Hebrew, he is the most important prophet in Judaism, he is an important prophet in Christianity, the Bahá'í Faith, a number of other Abrahamic religions. According to the Book of Exodus, Moses was born in a time when his people, the Israelites, an enslaved minority, were increasing in numbers and the Egyptian Pharaoh was worried that they might ally themselves with Egypt's enemies. Moses' Hebrew mother, secretly hid him when the Pharaoh ordered all newborn Hebrew boys to be killed in order to reduce the population of the Israelites. Through the Pharaoh's daughter, the child was adopted as a foundling from the Nile river and grew up with the Egyptian royal family.
After killing an Egyptian slavemaster, Moses fled across the Red Sea to Midian, where he encountered The Angel of the Lord, speaking to him from within a burning bush on Mount Horeb. God sent Moses back to Egypt to demand the release of the Israelites from slavery. Moses said that he could not speak eloquently, so God allowed Aaron, his brother, to become his spokesperson. After the Ten Plagues, Moses led the Exodus of the Israelites out of Egypt and across the Red Sea, after which they based themselves at Mount Sinai, where Moses received the Ten Commandments. After 40 years of wandering in the desert, Moses died within sight of the Promised Land on Mount Nebo. Jerome gives 1592 BCE, James Ussher 1571 BCE as Moses' birth year. In the Book of Deuteronomy, Moses was called "the man of God". Several etymologies have been proposed. An Egyptian root msy, "child of", has been considered as a possible etymology, arguably an abbreviation of a theophoric name, as for example in Egyptian names like Thutmoses and Ramesses, with the god's name omitted.
Abraham Yahuda, based on the spelling given in the Tanakh, argues that it combines "water" or "seed" and "pond, expanse of water", thus yielding the sense of "child of the Nile". The Biblical account of Moses' birth provides him with a folk etymology to explain the ostensible meaning of his name, he is said to have received it from the Pharaoh's daughter: "he became her son. She named him Moses, saying,'I drew him out of the water.'" This explanation links it to a verb mashah, meaning "to draw out", which makes the Pharaoh's daughter's declaration a play on words. The princess made a grammatical mistake, prophetic of his future role in legend, as someone who will "draw the people of Israel out of Egypt through the waters of the Red Sea."The Hebrew etymology in the Biblical story may reflect an attempt to cancel out traces of Moses' Egyptian origins. The Egyptian character of his name was recognized as such by ancient Jewish writers like Philo of Alexandria and Josephus. Philo linked Mōēsēs to the Egyptian word for water, while Josephus, in his Antiquities of the Jews, claimed that the second element, -esês, meant'those who are saved'.
The problem of how an Egyptian princess, known to Josephus as Thermutis and in Jewish tradition as Bithiah, could have known Hebrew puzzled medieval Jewish commentators like Abraham ibn Ezra and Hezekiah ben Manoah. Hezekiah suggested she either took a tip from Jochebed; the Israelites had settled in the Land of Goshen in the time of Joseph and Jacob, but a new pharaoh arose who oppressed the children of Israel. At this time Moses was born to his father Amram, son of Kehath the Levite, who entered Egypt with Jacob's household. Moses had one older sister and one older brother, Aaron; the Pharaoh had commanded that all male Hebrew children born would be drowned in the river Nile, but Moses' mother placed him in an ark and concealed the ark in the bulrushes by the riverbank, where the baby was discovered and adopted by Pharaoh's daughter, raised as an Egyptian. One day after Moses had reached adulthood he killed an Egyptian, beating a Hebrew. Moses, in order to escape the Pharaoh's death penalty, fled to Midian.
There, on Mount Horeb, God appeared to Moses as a burning bush, revealed to Moses his name YHWH and commanded him to return to Egypt and bring his chosen people out of bondage and into the Promised Land. During the journey, God tried to kill Moses because he had not circumcised his son, but Zipporah saved his life. Moses returned to carry out God's command, but God caused the Pharaoh to refuse, only after God had subjected Egypt to ten plagues did the Pharaoh relent. Moses led the Israelites to the border of Egypt, but there God hardened the Pharaoh's heart once more, so that he could destroy the Pharaoh and his army at the Red Sea Crossing as a sign of his power to Israel and the nations. After defeating the Amalekites in Rephidim, Moses led the Israelites to biblical Mount Sinai, where he was given the Ten Commandments from God, written on stone tablets. However, since Moses remained a long time on the mountain, some of the people feared that he might be dead, so they made a statue of a golden calf and worshiped it, thus disobeying and angering God and Moses.
Moses, out of anger, bro
In mathematics, a fractal is a subset of a Euclidean space for which the Hausdorff dimension exceeds the topological dimension. Fractals tend to appear nearly the same at different levels, as is illustrated here in the successively small magnifications of the Mandelbrot set. Fractals exhibit similar patterns at small scales called self similarity known as expanding symmetry or unfolding symmetry. One way that fractals are different from finite geometric figures is the way. Doubling the edge lengths of a polygon multiplies its area by four, two raised to the power of two. If the radius of a sphere is doubled, its volume scales by eight, two to the power of three. However, if a fractal's one-dimensional lengths are all doubled, the spatial content of the fractal scales by a power, not an integer; this power is called the fractal dimension of the fractal, it exceeds the fractal's topological dimension. Analytically, fractals are nowhere differentiable. An infinite fractal curve can be conceived of as winding through space differently from an ordinary line – although it is still 1-dimensional, its fractal dimension indicates that it resembles a surface.
Starting in the 17th century with notions of recursion, fractals have moved through rigorous mathematical treatment of the concept to the study of continuous but not differentiable functions in the 19th century by the seminal work of Bernard Bolzano, Bernhard Riemann, Karl Weierstrass, on to the coining of the word fractal in the 20th century with a subsequent burgeoning of interest in fractals and computer-based modelling in the 20th century. The term "fractal" was first used by mathematician Benoit Mandelbrot in 1975. Mandelbrot based it on the Latin frāctus, meaning "broken" or "fractured", used it to extend the concept of theoretical fractional dimensions to geometric patterns in nature. There is some disagreement among mathematicians about how the concept of a fractal should be formally defined. Mandelbrot himself summarized it as "beautiful, damn hard useful. That's fractals." More formally, in 1982 Mandelbrot stated that "A fractal is by definition a set for which the Hausdorff–Besicovitch dimension exceeds the topological dimension."
Seeing this as too restrictive, he simplified and expanded the definition to: "A fractal is a shape made of parts similar to the whole in some way." Still Mandelbrot settled on this use of the language: "...to use fractal without a pedantic definition, to use fractal dimension as a generic term applicable to all the variants". The consensus is that theoretical fractals are infinitely self-similar and detailed mathematical constructs having fractal dimensions, of which many examples have been formulated and studied in great depth. Fractals are not limited to geometric patterns, but can describe processes in time. Fractal patterns with various degrees of self-similarity have been rendered or studied in images and sounds and found in nature, art and law. Fractals are of particular relevance in the field of chaos theory, since the graphs of most chaotic processes are fractals; the word "fractal" has different connotations for laymen as opposed to mathematicians, where the layman is more to be familiar with fractal art than the mathematical concept.
The mathematical concept is difficult to define formally for mathematicians, but key features can be understood with little mathematical background. The feature of "self-similarity", for instance, is understood by analogy to zooming in with a lens or other device that zooms in on digital images to uncover finer invisible, new structure. If this is done on fractals, however, no new detail appears. Self-similarity itself is not counter-intuitive; the difference for fractals is. This idea of being detailed relates to another feature that can be understood without mathematical background: Having a fractal dimension greater than its topological dimension, for instance, refers to how a fractal scales compared to how geometric shapes are perceived. A regular line, for instance, is conventionally understood to be one-dimensional. A solid square is understood to be two-dimensional. We see that for ordinary self-similar objects, being n-dimensional means that when it is rep-tiled into pieces each scaled down by a scale-factor of 1/r, there are a total of rn pieces.
Now, consider the Koch curve. It can be rep-tiled into four sub-copies, each scaled down by a scale-factor of 1/3. So by analogy, we can consider the "dimension" of the Koch curve as being the unique real number D that satisfies 3D = 4, which by no means is an integer! This number is; the fact th
Paul the Apostle
Paul the Apostle known as Saint Paul and known by his Jewish name Saul of Tarsus, was an apostle who taught the gospel of Christ to the first-century world. Paul is considered one of the most important figures of the Apostolic Age and in the mid-30s to the mid-50s AD he founded several churches in Asia Minor and Europe, he took advantage of his status as both a Jew and a Roman citizen to minister to both Jewish and Roman audiences. According to writings in the New Testament and prior to his conversion, Paul was dedicated to persecuting the early disciples of Jesus in the area of Jerusalem. In the narrative of the Acts of the Apostles, Paul was traveling on the road from Jerusalem to Damascus on a mission to "arrest them and bring them back to Jerusalem" when the resurrected Jesus appeared to him in a great light, he was struck blind, but after three days his sight was restored by Ananias of Damascus and Paul began to preach that Jesus of Nazareth is the Jewish Messiah and the Son of God. Half of the book of Acts deals with Paul's life and works.
Thirteen of the twenty-seven books in the New Testament have traditionally been attributed to Paul. Seven of the Pauline epistles are undisputed by scholars as being authentic, with varying degrees of argument about the remainder. Pauline authorship of the Epistle to the Hebrews is not asserted in the Epistle itself and was doubted in the 2nd and 3rd centuries, it was unquestioningly accepted from the 5th to the 16th centuries that Paul was the author of Hebrews, but that view is now universally rejected by scholars. The other six are believed by some scholars to have come from followers writing in his name, using material from Paul's surviving letters and letters written by him that no longer survive. Other scholars argue that the idea of a pseudonymous author for the disputed epistles raises many problems. Today, Paul's epistles continue to be vital roots of the theology and pastoral life in the Catholic and Protestant traditions of the West, as well as the Orthodox traditions of the East.
Paul's influence on Christian thought and practice has been characterized as being as "profound as it is pervasive", among that of many other apostles and missionaries involved in the spread of the Christian faith. Martin Luther's interpretation of Paul's writings influenced Luther's doctrine of sola fide, it has been popularly assumed that Saul's name was changed when he became a follower of Jesus Christ, but, not the case. His Jewish name was "Saul" after the biblical King Saul, a fellow Benjamite and the first king of Israel. According to the Book of Acts, he was a Roman citizen; as a Roman citizen, he bore the Latin name of "Paul"—in biblical Greek: Παῦλος, in Latin: Paulus. It was typical for the Jews of that time to have one Hebrew, the other Latin or Greek. Jesus called him "Saul, Saul" in "the Hebrew tongue" in the book of Acts, when he had the vision which led to his conversion on the Road to Damascus. In a vision to Ananias of Damascus, "the Lord" referred to him as "Saul, of Tarsus".
When Ananias came to restore his sight, he called him "Brother Saul". In Acts 13:9, Saul is called "Paul" for the first time on the island of Cyprus—much than the time of his conversion; the author indicates that the names were interchangeable: "Saul, called Paul." He thereafter refers to him as Paul Paul's preference since he is called Paul in all other Bible books where he is mentioned, including those that he authored. Adopting his Roman name was typical of Paul's missionary style, his method was to put people at their ease and to approach them with his message in a language and style to which they could relate, as in 1 Cor 9:19–23. The main source for information about Paul's life is the material found in Acts. However, the epistles contain little information about Paul's pre-conversion past; the book of Acts recounts more information but leaves several parts of Paul's life out of its narrative, such as his probable but undocumented execution in Rome. Some scholars believe Acts contradicts Paul's epistles on multiple accounts, in particular concerning the frequency of Paul's visits to the church in Jerusalem.
Sources outside the New Testament that mention Paul include: Clement of Rome's epistle to the Corinthians. Paul was born between the years of 5 BC and 5 AD; the Book of Acts indicates that Paul was a Roman citizen by birth, but Helmut Koester takes issue with the evidence presented by the text. He was from a devout Jewish family in the city of Tarsus, one of the largest trade centers on the Mediterranean coast, it had been in existence several hundred years prior to his birth. It was renowned for its university. During the time of Alexander the Great, who died in 323 BC, Tarsus was the most influential city in Asia Minor. Paul referred to himself as being "of the stock of Israel, of the tribe of Benjamin, a Hebrew of the Hebrews; the Bible reveals little abou
Lightning is a violent and sudden electrostatic discharge where two electrically charged regions in the atmosphere temporarily equalize themselves during a thunderstorm. Lightning creates a wide range of electromagnetic radiations from the hot plasma created by the electron flow, including visible light in the form of black-body radiation. Thunder is the sound formed by the shock wave formed as gaseous molecules experience a rapid pressure increase; the three main kinds of lightning are: created either inside one thundercloud, or between two clouds, or between a cloud and the ground. The 15 recognized observational variants include "heat lightning", seen but not heard, dry lightning, which causes many forest fires, ball lightning, observed scientifically. Humans have deified lightning for millennia, lightning inspired expressions like "Bolt from the blue", "Lightning never strikes twice", "blitzkrieg" are common. In some languages, "Love at first sight" translates as "lightning strike"; the details of the charging process are still being studied by scientists, but there is general agreement on some of the basic concepts of thunderstorm electrification.
The main charging area in a thunderstorm occurs in the central part of the storm where air is moving upward and temperatures range from −15 to −25 °C, see figure to the right. At that place, the combination of temperature and rapid upward air movement produces a mixture of super-cooled cloud droplets, small ice crystals, graupel; the updraft carries the super-cooled cloud droplets and small ice crystals upward. At the same time, the graupel, larger and denser, tends to fall or be suspended in the rising air; the differences in the movement of the precipitation cause collisions to occur. When the rising ice crystals collide with graupel, the ice crystals become positively charged and the graupel becomes negatively charged. See figure to the left; the updraft carries. The larger and denser graupel is either suspended in the middle of the thunderstorm cloud or falls toward the lower part of the storm; the result is that the upper part of the thunderstorm cloud becomes positively charged while the middle to lower part of the thunderstorm cloud becomes negatively charged.
The upward motions within the storm and winds at higher levels in the atmosphere tend to cause the small ice crystals in the upper part of the thunderstorm cloud to spread out horizontally some distance from thunderstorm cloud base. This part of the thunderstorm cloud is called the anvil. While this is the main charging process for the thunderstorm cloud, some of these charges can be redistributed by air movements within the storm. In addition, there is a small but important positive charge buildup near the bottom of the thunderstorm cloud due to the precipitation and warmer temperatures. A typical cloud-to-ground lightning flash culminates in the formation of an electrically conducting plasma channel through the air in excess of 5 km tall, from within the cloud to the ground's surface; the actual discharge is the final stage of a complex process. At its peak, a typical thunderstorm produces three or more strikes to the Earth per minute. Lightning occurs when warm air is mixed with colder air masses, resulting in atmospheric disturbances necessary for polarizing the atmosphere.
However, it can occur during dust storms, forest fires, volcanic eruptions, in the cold of winter, where the lightning is known as thundersnow. Hurricanes generate some lightning in the rainbands as much as 160 km from the center; the science of lightning is called fulminology, the fear of lightning is called astraphobia. Lightning is not distributed evenly around the planet. On Earth, the lightning frequency is 44 times per second, or nearly 1.4 billion flashes per year and the average duration is 0.2 seconds made up from a number of much shorter flashes of around 60 to 70 microseconds. Many factors affect the frequency, distribution and physical properties of a typical lightning flash in a particular region of the world; these factors include ground elevation, prevailing wind currents, relative humidity, proximity to warm and cold bodies of water, etc. To a certain degree, the ratio between IC, CC and CG lightning may vary by season in middle latitudes; because human beings are terrestrial and most of their possessions are on the Earth where lightning can damage or destroy them, CG lightning is the most studied and best understood of the three types though IC and CC are more common types of lightning.
Lightning's relative unpredictability limits a complete explanation of how or why it occurs after hundreds of years of scientific investigation. About 70 % of lightning occurs over land in the tropics; this occurs from both the mixture of warmer and colder air masses, as well as differences in moisture concentrations, it happens at the boundaries between them. The flow of warm ocean currents past drier land masses, such as the Gulf Stream explains the elevated frequency of lightning in the Southeast United States; because the influence of small or absent land masses in the vast stretches of the world's oceans limits the differences between these variants in the atmosphere, lightning is notably less frequent there than over larger landforms. The North and South Poles are limited in their coverage of thunderstorms and theref