ejaasaari/simplewiki-2025-04-01 huggingface dataset:
Light is a form of electromagnetic radiation. It is natural agent that stimulates sight and makes things easy to see. Light is the opposite of darkness. Light has a wavelength. Some wavelengths can be seen by the human eye. Others cannot. Many animals can see light. They need it to find food, water, and other things. Light makes up a part of both the electromagnetic spectrum and radiation given by stars, like the sun. The light that comes from the sun reaches the Earth and makes it bright. This is called daytime. The study of light is known as optics. When light hits an opaque object, it makes a shadow. When light hits a transparent object, it passes through it almost completely without making a significant shadow. Light is a form of electromagnetic radiation that shows properties of both waves and particles. It is a form of energy. Light also keeps the Earth warm. Light exists in tiny energy packets called photons. Each wave has a wavelength or frequency. The human eye sees each wavelength as a different color. Rainbows show the entire spectrum of visible light. The separate colors, moving in from the outer edges, are red, orange, yellow, green, blue, indigo and violet. Other colors can be seen only with special cameras or instruments: Wavelengths up the frequency of red are called infrared, and higher than of violet are called ultraviolet. The main properties of light are intensity, polarization, phase and orbital angular momentum. In physics, the term "light" sometimes means electromagnetic radiation of any wavelength, whether it can be seen or not. Physical properties of light. In a vacuum, the speed of light is 299,792,458 meters per second, or about 186,282 miles per second. This means it takes about 8 minutes for light to reach Earth from the Sun.  Light moves in a straight line. The straight line path is often drawn as a ray that moves in one direction. Ray diagrams are used to illustrate light traveling from one place to another. A beam of light can be thought of as a set of light rays. Objects that block rays of light can create shadows. Opaque objects block all light rays and create a darker shadow. Translucent objects block some rays
Stockholm is the capital city of Sweden. It is also the biggest city in Sweden. It is on the east coast of the country. The city is built on islands, with canals and open water in the inner city. Stockholm is found between Sweden's third largest lake, Mälaren, and the Baltic Sea. Tyresta National Park is near Stockholm. Geography. Central Stockholm has four different parts - Kungsholmen, Södermalm, Norrmalm and Östermalm. It is built on 14 islands connected by 57 bridges. Kungsholmen and Södermalm are islands, while Norrmalm and Östermalm are parts of the mainland. Also, there are several smaller islands in the inner city - Gamla Stan, Riddarholmen, Djurgården and Skeppsholmen. Since Stockholm has so many islands, it is sometimes referred to as the "Venice of the North". Gamla Stan is the oldest part of the city - the name means "Old Town", and is usually called that in English. Djurgården is mostly a large park, but there are buildings on the island. Most of these are museums that commemorate Sweden's and Stockholm's past - like Skansen, a zoo with a Swedish theme. Skeppsholmen is an island that used to be a training ground and military school, but most of the buildings are now used for museums and art galleries, such as the Modern Museum, or the East Asian museum. Riddarholmen is a part of Gamla Stan, but actually a different island. All of the islands in Stockholm are connected by several bridges. The biggest one is Västerbron, going from Kungsholmen to Södermalm. History. Birger Jarl is considered the founder of Stockholm. It is believed that he rebuilt a defense building in the 13th century on what is today the island of the Old town. Around the fortification, a town grew. The town grew mainly because of its sea and land trading. Wikimania. The last Wikimania conference is hosted in this city in 2019.
Rain is a kind of precipitation. Precipitation is any kind of water that falls from clouds in the sky, like rain, hail, sleet and snow. It is measured by a rain gauge.  Overview. Rain is part of the water cycle. Clouds will often absorb smoke to create rain, commonly referred to as "nature's laundry" due to this process. Some places have frequent rain. This makes rainforests. Some have little rain. This makes deserts. Types. Rainstorm. A rainstorm is a sudden heavy fall of rain. It may cause flash floods in valleys. Heavy rain for a long time may make floods that destroy houses and cause drowning. Also, landslides may happen. Convectional rain. When the Sun heats the Earth's surface, the ground heats the air above it. Convection makes the air rise and cool. When it cools to the dew point, clouds form and rain follows. This usually occurs on flat land. This type of rainfall often causes summer showers and thunderstorms. Relief rain. Relief rain typically occurs along coastal areas where a line of hills runs along the coast. Wet onshore wind from the sea meets a mountain, hill or any other sort of barrier, it is forced to rise along the slope and cools. When the air temperature falls to its dew point, water vapour condenses to form clouds. When the clouds can no longer hold the water droplets, relief rain begins to fall on the windward slope of the mountain. On the leeward slope, air sinks, it is warmed and further dried by compression. Therefore, the leeward slope is known as rain shadow. Moist winds blow in from the sea and are forced to rise over the land. The air cools and the water vapour condenses, forming raindrops. Places that reactive a lot of rain in the world are places that have relief rainfall.  Frontal rain. Frontal rain, also known as cyclonic rain, happens when cooler air and warmer, humid air meet in a weather front. The less dense warm air rises and condenses forming clouds. These clouds grow and eventually create rain. In some places on the northern temperate zone the cold
2009 (MMIX) was a common year starting on Thursday in the Gregorian calendar, the 2009th year of the Common Era (CE) and "Anno Domini" (AD) designations, . 2009 was called the: 2009 was the Chinese Year of Earth Ox based on the 12-year Chinese Zodiac cycle.
Gambling is a contest where a player bets on the result of an event. The bet is generally in the form of money. The rules and the amount of money bet have to be decided on before the event happens. History. Playing cards appeared in the 9th century AD in China. Records trace gambling in Japan back at least as far as the 14th century. Poker, the most popular U.S. card game associated with gambling, derives from the Persian game As-Nas, dating back to the 17th century. The first known casino, the Ridotto, started operating in 1638 in Venice, Italy. Types. There are three variables common to all gambling. There are many types of gambling. Casino games, sports betting (especially horse racing), and state lotteries are some of the most common forms of gambling. Investments, such as stocks, bonds and real estate, are also sometimes considered forms of gambling. Generally, the odds are not in favor of the gambler. Issues. Many people gamble for fun and entertainment. For others it can become an addiction and lead to financial problems.  Gambling addiction is a serious mental health issue which can become life-threatening. People with a gambling problem should seek help. Many organizations are trying to combat gambling addiction. One project to combat addiction is the Global Self-Exclusion Initiative, which helps people stop gambling. Rules. Gambling regulation differs in different countries. Some have established specific legal institutions. However, some countries have only overseeing laws. A well-known executive institution is The Gambling Commission in the UK. Its main function is controlling commercial gambling in partnership with people in charge of licensing. An example of strict ruling is the Gambling Law in the USA. The law decides gaming rules for local, state, and federal businesses. In the United States, gambling is restricted almost everywhere, except in Las Vegas and in Atlantic City, New Jersey. New Jersey, legalised online gambling and poker in November 2013. In 2018, Swiss citizens voted that gambling should also be allowed on the Internet in the future. A convincing 73% voted in the referendum, in which 1.8 million Swiss people took part. The new Gaming Act was put into
Monty Python, also known as The Pythons, is a group of British comic actors. They have acted in several comedy movies (most famously, Monty Python and the Holy Grail). They had a television show, "Monty Python's Flying Circus" between 1969 and 1974, which is still well-known and watched around the world. The members of Monty Python are: John Cleese, Eric Idle, Graham Chapman, Terry Gilliam, Terry Jones, and Michael Palin. Carol Cleveland and Neil Innes regularly appeared in their movies.  Monty Python started with their first movie, "And Now For Something Completely Different", and finished with their final movie, "Monty Python's The Meaning of Life".
Time zones give specific areas on the Earth a time of day that is earlier or later than the neighboring time zones. This is because when it is daytime on one side of the earth, it is night-time on the other side. There are 24 time zones dividing the earth into different times, each with its own name, like the North American Eastern Time Zone. The North American Eastern Time Zone contains large cities in North America like New York City and Miami. Greenwich Mean Time (GMT) began in 1675. This was when the Royal Observatory, Greenwich was built to help ships find their longitude at sea. GMT was a standard reference for time keeping when each city kept a different local time. When railways began carrying many people quickly among cities keeping different time, they adopted time zones to simplify operations. By about 1900, almost all time on earth was in the form of standard time zones.  Greenwich Mean Time is now called UTC (Coordinated Universal Time). UTC is the time standard of the world. All other parts of the world are offset (plus or minus) according to their longitude. Most of the zones are offset by a full hour, but there are some offset by half an hour or 45 minutes. In some parts of the world they follow the Daylight Saving Time (DST), and during this period of time in summer they add one hour to their normal solar hour. In the poles, the time is UTC in the North Pole and UTC+12 in the South Pole. The time zones are numbered in relation to the UTC, so in Los Angeles the time zone will be UTC−8, in London UTC+0, in Rome UTC+1, and in New Delhi UTC+5:30.
A market is a place where people go to buy or sell things. When people have products to sell, they set up a market place. There may be a special building for the market place, or the market may be held in an open space where the sellers can put up a stall (like a kind of tent) and then take the stall down at the end of the day. The word "market" can also have a more general meaning in the economy. It can mean the way things are bought or sold. "There is a big market for dishwashers" means that lots of people want to buy dishwashers. Therefore, a business that makes dishwashers is likely to be able to make a lot of money. When things are sold, people buy the product, and this "stimulates the economy" (helps people to spend and earn money). The market needs to balance supply and demand. There is no reason to make a supply of dishwashers if people do not want dishwashers. In the market, prices may change quickly if supply or demand changes. Competition. If a seller of a good cannot supply what customers want or asks for a very high price, other sellers may try to supply that good. If other sellers enter the market for that good, in competition, that will tend to fulfill demands and lower prices. Sellers who do not like competition may try to kill their competition. When there is no competition, a monopoly is formed. Many countries have laws to protect the free market from monopolies.
An electron is a very small piece of matter. Its symbol is e−, and it was discovered by J. J. Thomson in 1897. The electron is a subatomic particle. Every atom is made of some electrons that surround the nucleus of the atom. An electron can also be separate from any atom. It is believed to be an elementary particle because it cannot be broken down into anything smaller. Its electric charge is negative. Electrons have very little mass (little weight) so very little energy is needed to move them fast. They may move almost at the speed of light, for instance, as beta particles, and in the inner electron shells of elements with a large atomic number.  Electrons take part in gravitational, electromagnetic and weak interactions. The electromagnetic force is strongest in common situations. Electrons repel (push apart) from each other because they have the same electric charge. Electrons are attracted to protons because they have opposite electric charge. An electron has an electric field, which describes these forces. The electricity that powers televisions, motors, mobile phones, basically everything (electric) is actually many electrons moving through wires or other conductors. Description. Electrons have the smallest electrical charge. This electrical charge equals the charge of a proton, but has the opposite sign. For this reason, electrons are attracted towards the protons in atomic nuclei. This attraction makes electrons near a nucleus form an atom. An electron has a mass of about 1/1836 times a proton. One way to think about the location of electrons in an atom is to imagine that they orbit at fixed distances from the nucleus. This way, electrons in an atom exist in a number of electron shells surrounding the central nucleus. Each electron shell is given a number 1, 2, 3, and so on, starting from the one closest to the nucleus (the innermost shell). Each shell can hold up to a certain maximum number of electrons. The distribution of electrons in the various shells is called electronic arrangement (or electronic form or shape). Electronic arrangement can be shown by numbering or an electron diagram. (A different way to think about the location of electrons is to use quantum mechanics to calculate their atomic orbitals
Chile, officially the Republic of Chile, is a country on the south-western side of South America. Most people there speak Spanish. Chile, which claims a part of the Antarctic continent, is the longest country on earth. The Atacama Desert, in the north of the country, is the driest place on earth. The average rainfall there is less than per year. The center of Chile, with the two cities Santiago and Valparaíso, has a Mediterranean climate with an average temperature of in January and in July. In the middle of Chile, the country is very good for growing things. There are about 16.9 million people living in Chile in 2009. About 10 million people live in the center of Chile around Valparaíso and Santiago, on about 20% of the total land. Chile is a well-educated country. Only 2.7% are not able to read or write. Some believe that Chile has one of the best school systems in South America. About 95% of Chileans are people with a combination of European descent, mostly Spanish, but also German, English, Italian and Arab people. Around 2% of the population is Native American, but most people have native ancestors. Immigrants are 7% of the population. including Peruvians, Bolivians, Colombians, Haitians, Chinese and Europeans. The majority of people are Roman Catholic (62.8%), but many do not go to church. About 10% are Protestant, and there are some Jews and Muslims as well. The country's official language is Spanish. Chili peppers, first cultivated by Native Americans from other Latin American countries and the United States, did not come from this country, although it has a similar name. Chile's currency is the Chilean "peso". Geography. Chile borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far south. It is over north to south, but only at its widest point east to west. The northern Atacama Desert has great mineral wealth, mostly copper and nitrates. Chile is the largest producer of copper. The Andes Mountains are on the
An ambassador is a person sent by the government of a country to a different country. The ambassador is the official representative of their country. The ambassador speaks to officials of the other country about any problems and issues between the two countries. In past years, communication between countries could take days or weeks. It was necessary to have a person in each foreign capital to have meetings and make negotiations between countries. Nowadays, communication is much faster, and often governments can be in direct contact with each other. However, it is still true that many problems need person-to-person meetings, so ambassadors are still needed. Often an ambassador will live in the foreign country for a number of years. An embassy is where the ambassador lives. Embassies are most often in the capital of the foreign country. An ambassador may bring people with him to help him and work at the embassy. Some of the high ranking people may be called embassy officials. It is both tradition and law that the ambassador and many embassy officials have diplomatic immunity. They cannot be arrested or prosecuted in the foreign country. The only possibility is to send a person back to their own country.
Monday is a day of the week. In some countries, it is the second day of the week. In other parts of the world, including some countries in Europe, Monday is the first day of the week. Monday is the day in which is celebrated Easter Monday. The International Standards Organization considers Monday the first day of the week.
A nuclear war is a war in which countries fight with nuclear weapons. Because nuclear weapons are extremely powerful and could cause destruction throughout the world, the possibility of nuclear war has had a great effect on international politics. So far, two nuclear weapons have been used during warfare. They were used in the atomic bombings of Hiroshima and Nagasaki and resulted in the deaths of approximately 120,000 people. Thousands of much more powerful bombs were made in later years. They have not yet been used in war.  History. Nuclear bombs were invented by the United States with Canadian and British help during World War II to help make that war stop. The destruction of Hiroshima and Nagasaki and the Soviet invasion of Manchuria caused Japan to surrender. They are still the only nuclear weapons that have ever been used in fighting a war. At that time only the United States had the technology needed to make these bombs, but within a few years the Soviet Union had developed it too. In the new Cold War, the United States and the Soviet Union were enemies and each had many nuclear weapons, but they did not dare to use them against each other, either directly or by attacking the other country's allies. Since either country could be completely destroyed by the other's weapons, nuclear war could no longer be limited to the use of only one or two bombs; if they were used anywhere by one side, the other would attack with its own nuclear weapons, and the fighting would almost certainly become greater. This situation came to be known as the "balance of terror," or Mutually Assured Destruction, and stopped conflicts between the two superpowers from leading to a third world war. Since the end of Communist rule in Russia and Eastern Europe, tensions between America and Russia have eased and war has become less likely. However, today there is more worry about nuclear proliferation. Countries around the world who already have their own bombs include Britain, France, China, Israel, India, Pakistan and North Korea; as all kinds of technology tend to become cheaper and easier to get and use, there is a fear that nuclear weapons could become available to countries with unstable governments. There is also the possibility that terrorists might be able to capture or build nuclear weapons and use them
Tax is money that people have to pay to the government. The government uses the money it gets from taxes to pay for things. For example, taxes are used to pay for people who work for the government, such as the military and police, provide services such as education and health care, and to maintain or build things like roads, bridges and sewers. The earliest known taxes were those of the Egyptian Old Kingdom.  Types of taxes. There are many different kinds of taxes. They may be direct tax or indirect tax. Taxes can also be split into 3 groups: Paying lots of different taxes. Often because different parts of governments use taxes for different things, people end up paying lots of taxes. In the United States, for example, the national government has an income tax; most states have an income tax or a sales tax, or both; and cities and towns may have a sales tax or a property tax. In some states such as Ohio, the sales tax is different in each county. Before Taxes. In ancient times, people from one city or area would attack another place, and make the people there pay "tribute". Tribute meant that the attacked people would pay money (or other things), and the attacker would stop attacking them. A famous tribute was the Danegeld, when people from Denmark conquered part of England and made the English pay thousands of silver coins. Groups who are against taxes. Anarchists and Libertarians are against all taxes or against high taxes. As people are paying them unwillingly and under the threat of sanctions, they say that taxation is the same as robbery. (Taxation as theft)
Florida ( ), is a state in the southeast part of the United States. It is the 22nd largest US state by total area with 65,757.70 sq mi (170,312 km2) and the third most-populous with a 2020 population of more than 21 million. It is a peninsula, which means that water surrounds the state on three of four possible sides. To the west is the Gulf of Mexico, to the south is the Florida Straits, and to the east is the Atlantic Ocean. It also borders two states, Alabama and Georgia, both along its northern border. The highest elevation in Florida is Britton Hill. Many Cubans, Haitians and other Caribbeans live in state. In 2018, The top countries of origin for Florida’s immigrants were Cuba, Haiti, Colombia, Mexico and Jamaica. History. Native Americans had first settled in Florida before the arrival of the Europeans. Florida had many residents from many tribes and nations living in almost all parts of it for thousands of years. These include the Timucua, the Tequesta, the Calusa, the Seminole, the Miccosukee, and many more. Florida was first discovered by a European in 1513 by the Spanish Ponce De Leon, who called this peninsula "Tierra de la Pascua Florida" (Land of the Easter flowered) because it was discovered on Easter: in the next centuries only the last word remained. Northern Florida contains hills because it is at the very end of the Appalachian Mountains. The highest hill in Florida is Britton Hill, in northern Walton County near the town of Lakewood, Florida. It is above sea level. It is the shortest of the highest points in all other states. Florida has the longest coastline in the continental United States.The Gulf Stream ocean current goes through the Atlantic Ocean near the east coast of Florida, so the water is warmer than the Pacific Ocean. The Gulf of Mexico is on the west coast of Florida. In the center of southern Florida is a lake called Lake Okeechobee. It is the seventh largest freshwater lake in the United States and the second largest freshwater lake entirely within the lower 48 states