cahya/wikipedia-simple-en huggingface dataset:
Kahoolawe

Kahoolawe is the smallest of the eight main volcanic islands of Hawaii.  It is west of Maui and south of Lanai.  It is roughly 11 miles long by  across (). The highest point, Lua Makika, is  above sea level. The island is dry because its low elevation does not cause much rain (orographic precipitation) to fall from the northeastern trade winds.

Kahoolawe was used as a gunfire and bombing target by the United States military during World War II.  It was a defense training area by the United States Navy from around 1941 until May 1994.  Popular opinion in the state against this practice brought the end to this use. Navy has since been trying to cleanup unexploded ordnance (bombs and explosive shells) from the island.  Ordnance is still buried or lying on the ground. Other items have washed down gullies and still other unexploded ordnance is underwater offshore. In 1981, the entire island was included on the National Register of Historic Places.

The island is planned to be given back to the Hawaiian people.  In 1993, the U.S. Congress passed a law that "recognized the cultural importance of the island, required the Navy to return the island to the State, and directed the Navy to do an unexploded ordnance (UXO) cleanup and environmental restoration"  . The turnover officially occurred on November 11, 2003, but the cleanup has not yet been completed. The U.S. Navy was given $400 million and 10 years to complete the large cleanup task, but this work has gone much slower than planned.

In 1993, the Hawaii State Legislature established the Kahoolawe Island Reserve. It is made up of the whole island and waters out to  from shore. By State Law, Kahoolawe and its waters can only be used for Native Hawaiian cultural, spiritual, and subsistence purposes; fishing; environmental restoration; historic preservation; and education. Commercial uses are not allowed. The Legislature also created the Kahoolawe Island Reserve Commission (KIRC) to manage the Reserve while it is held in trust for a "future Native Hawaiian Sovereignty entity"  . 

After the cleanup is finished, the restoration of Kahoolawe will need ways to control erosion, restore the plant life, recharge the water table, and slowly replace alien plants with native ones. Plans will include methods for damming gullies and reducing rainwater runoff. Non-natives will temporarily stabilize some areas before the permanent planting of native plants.

Other websites 
http://www.state.hi.us/kirc/main/home.htm 

Islands of Hawaii
Volcanoes of Hawaii
Killing

Killing a living thing is when someone or something ends that life and makes the living thing die. It means causing a death. When a human being kills another human being, it is called murder or homicide, such as manslaughter.  

Pesticides and herbicides are poisons for killing bad wild small animals or plants, respectively.

When a soldier kills another in war, it is called "combat".  When the state kills a convict sentenced to capital punishment, it is called execution. When someone kills a  powerful person it is called assassination. When a person who wants to die kills himself it is suicide, or euthanasia if killed by another. When people kill other people to eat them, it is called cannibalism.

Related pages 
 Cain and Abel

Crime
Kilometre

The kilometre is a common unit used for longer distances on Earth. The international unit for measuring distances is the metre and a kilometre is 1000 metres. It is used in some countries for measuring road and sea distances. In the UK and the USA, the mile is used more than kilometres for road distances and the nautical mile for sea distances.

It is often used to measure the speed of cars, planes and boats by saying how many kilometres it can travel in an hour. This is shown as km/h.

It is also spelled kilometer. This spelling is used in American English.

One kilometre is 0.6214 miles (3280.84 feet). This means that one mile is 1.6093 kilometres.

One kilometre is the approximate distance a healthy adult human being can walk in ten minutes.

Related pages
 Yard (unit of length)

Units of length
Leisure

Leisure (or free time) is when a person can choose what to do. During a person's leisure time, they do not have an obligation to be at school or work at a job. During leisure time, people can do fun activities, family activities, or other non-work activities, such as hobbies.  

Common forms of recreation or leisure are:

 Playing sports such as football or hockey
 Playing games such as chess or cards
 Exercising such as running or lifting weights
 Watching television and movies
 Listening to music
 Hobbies such as playing piano or guitar, knitting, or sewing
 Travelling
 Reading

A vacation or holiday is the setting aside of time specifically for leisure. During their vacation, some people travel to a different region or country, and stay at a hotel so that they can do things they could not do near home. Other people prefer to spend their vacation time at home in their own community.

In rich industrialized countries such as the US and Canada, as well as in most European countries, workers are allowed to stay home on the weekend (usually Saturday and Sunday), and use it as leisure time. People in poorer developing countries usually have less leisure time, as they have to work longer hours and more days per year.
Live

Live can be a verb. It rhymes with "give". "To live" means "to be alive" (and not dead). If you live, then you have life.
  
It can be used in a general way: 
"I live in London". 
"I live in a house". 
"A person can always live in fear". 

Live can be an adjective. It rhymes with "five".
In television, a "live" program is one where what is happening can be seen at the same time as it is happening. Sports program are usually "live". 
In music, If a CD is a "live recording" it means a recording which was made at a concert with an audience present. If it is not a live recording it may be a recording made in a studio.
Live album
"Live" can also mean "full of energy" or simply "happening now". Something that is being talked about in the newspapers at the moment can be a "live issue".

VOA Special English words
List of countries

This is a list of sovereign states.

References

Notes
Provinces and territories of Canada

Canada, a country and sovereign state in the northern part of North America, is made up of thirteen administrative divisions: ten provinces and three territories. The different levels of government in Canada are based on the principles of a federation: those of each of the provinces and territories share power with the federal government. The territories' governments have a more limited set of powers versus the federal government than that of the provinces'.

The provinces are in the south of Canada, near the border with the United States. They go from the Atlantic Ocean in the east to the Pacific Ocean in the west. The territories are to the north, where fewer people live, close to the Arctic Circle and Arctic Ocean.

Here is a list of the provinces and territories, and their standard abbreviations, with their capitals (the cities where their governments are based) and largest cities. Canada's national capital, where the federal government meets, is Ottawa.

References

 
Canada-related lists
Las Vegas

Las Vegas is a city in the American state of Nevada. There were 640,932 people living in the city in 2015, and more than 2,000,000 people living in the metropolitan area. It is the largest city in Nevada. Las Vegas is also the county seat of Clark County. Carolyn Goodman became the mayor in 2011.

Politics 
Las Vegas leans to the left. Three of the four congressional districts in Nevada include parts of Las Vegas, and all three congresspeople representing those districts are Democrats from Las Vegas.

History 
Native Americans were the first to reside in the area, specifically the Paiute tribe. It was first called Las Vegas (which means The Meadows in the Spanish language) by the Spanish. The city is known for its dry weather, as is the rest of southern Nevada. It is surrounded by desert. 

The US Army built Fort Baker there in 1864. Las Vegas has natural springs, where people used to stop for water when they were going to Los Angeles or other places in California.

In 1905, 110 acres owned by William A. Clark, on which he built a railroad to Southern California were auctioned and Las Vegas was founded as a railroad town. Las Vegas officially became a city in 1911.

References 

 
County seats in Nevada
1905 establishments in the United States
20th-century establishments in Nevada
Leap year

A leap year is a year in which an extra day is added to the Gregorian calendar, which is used by most of the world. A common year has 365 days, but a leap year has 366 days. The extra day, February 29, is added to the month of February. In a common year, February has 28 days, but in a leap year it has 29 days. The extra day, called a leap day, occurs on the same day of the week as the first day of the month, February 1.

Leap years are evenly divisible by 4. The most recent leap year was 2020 and the next leap year will be 2024. However, any year that is evenly divided by 100 would not be a leap year unless it is evenly divided by 400. This is why 1600, 2000, and 2400 are leap years, while 1700, 1800, 1900, 2100, 2200, and 2300 are common years, even though they are all divisible by 4.

We have leap years because instead of 365 days, the Earth really takes a few minutes less than 365-1/4 days (365.24219) to go completely around the Sun. Without leap years, the seasons would start one day earlier on the calendar every four years. After 360 years, spring in the Northern Hemisphere and autumn in the Southern Hemisphere would begin on December 21 (which is when winter in the Northern Hemisphere and summer in the Southern Hemisphere presently begins).

A number of countries use a lunar calendar (based on the Moon, instead of the Sun, like our solar calendar is). They have leap years when they add an extra lunar month. Different calendars add the extra month in different ways. So a year which has 366 days instead of 365 days where the month of February has 29 days is called a leap year.

In a leap year, the corresponding months are January, April, and July, February and August, March and November, and September and December. No month corresponds to May, June, or October.

In the Gregorian calendar, 97 out of every 400 years are leap years. In the outdated Julian calendar, 100 years out of every 400 are leap years. All other years are common years.

Related pages 
 February 29
 Common year
 Century leap year

Years
Leather

Leather is the skin of an animal made into a durable material by tanning. The skins of cows, pigs, and goats are often used to make leather. Skins of snakes, alligators or crocodiles, and ostriches are sometimes used to make fancier leather. Shoes, bags, clothes, and balls are often made of leather. Sometimes people make leather out of whales, ducks, giraffes, and African elephants, but all of these ways of making leather are very simple but can also be very hard and rare sometimes.

How leather is made
The way leather is made is divided into three processes. They are preparing the leather, tanning it, and crusting.

In preparing the leather, many things are done to make it ready for tanning. They include soaking it, removing the hair, liming, deliming, bating, bleaching, and pickling.

Tanning is a process that makes the proteins, especially collagen, in the raw hide stable. It increases the thermal and chemical stability of the animal skins. The difference between fresh and tanned animal skin is that fresh animal skin dries to make it hard and stiff. When water is added to it, it becomes bad. But, animal skin that is tanned dries to make it flexible. It does not become bad when water is added to it.

Crusting is a process that makes the leather thin and lubricates it. Chemicals added when crusting must be set in place. Crusting ends with drying and making the leather soft. It may include splitting, shaving, dyeing, whitening or other methods.

From other animals
Today, most leather is made from the skin of cattle, which makes up about 65% of all the leather made. Other animals that are used include sheep (about 13%), goats (about 11%), and pigs (about 10%).

Horse skin is used to make strong leather. Lamb and deerskin are used for soft leather. It is used in work gloves and indoor shoes.

Kangaroo leather is used to make things that must be strong and flexible. It is used in bullwhips.

In Thailand, stingray leather is used in wallets and belts. Stingray leather is tough and durable.

Natural materials
License

A (license for American English) or (licence for British English) allows someone to do something that they otherwise are not allowed to do. A person usually has to pay some money, and maybe pass a test to get a license. A license is usually written but it does not have to be. Most kinds of licenses can only be used by the person they were given to. Licenses may be temporary or permanent. Some licenses can not be taken away once they are given. A person with a license is called a licensee.

In many countries, if a person tries to do something without the correct license to do it, they might have to pay a fine or go to prison.

Examples of licenses
There are many different types of licenses.

Driver's license
The laws of most countries say that people are only allowed to drive cars if they have a driver's license.  If a person does not have a license, they may have to pay a fine if they are caught by the police.  In many countries, a person must take a test and pay money to get a license. The test would check that they know the road rules, and have the skill to drive a car.

Hunting license
Other licenses give permission to shoot animals (often called a hunting license). The hunting license usually says when a person may hunt. A hunter may have to pass a test to show that they understand the rules about hunting.

Television licence
In the United Kingdom and the Republic of Ireland, if someone has a television set, they must buy a "television licence" every year.

Copyright licenses 
Copyright is a law that gives the owner of a creative work the right to decide what other people can do with it. A person or a company can give a license to a copyright that they own. So in order for another person to use an owner's copyright they need permission from the owner. For example, when someone buys computer software, they also need a license from the creator of the software (a copyright owner) allowing the buyer to use the software.

Difference between license and licence 
"License" is a verb and "licence" is a noun. "Licensing sessions" were the meetings of magistrates which decided about giving licences to sell alcohol.  

In American English there is no difference in spelling between the verb "to license"  meaning to give permission, and the noun "a license" meaning the permission to do something.

Distinction between a licence and a qualification 
A degree in medicine is a qualification showing a person has successfully studied medicine. It is awarded for life. A licence to practice medicine is a legal permission to do so within the territory covered by the licensing authority. The licence may be taken away ('revoked') in certain situations.

Related pages 
 Copyright
 Patent
 Trademark

References 

Law
Political divisions of China

There are twenty-three provinces, four municipalities, five autonomous regions and two special administrative regions in the People's Republic of China. The island of Taiwan is claimed as a province by the People's Republic of China (PRC), but it is not under their control. Taiwan is an island known as Republic of China (Taiwan).

Provinces 
There are 23 provinces in the People's Republic of China.
 Anhui
 Fujian
 Gansu
 Guangdong
 Guizhou
 Hainan
 Hebei
 Heilongjiang
 Henan
 Hubei
 Hunan
 Jiangsu
 Jiangxi
 Jilin
 Liaoning
 Qinghai
 Shaanxi
 Shandong
 Shanxi
 Sichuan
 Taiwan*
 Yunnan
 Zhejiang

* The island of Taiwan is claimed as a province by the People's Republic of China (PRC), but it is not under their control. Taiwan is an island known as Republic of China (Taiwan).

Municipalities 
There are 4 municipalities in the People's Republic of China. "Municipality" is the common English name for the Chinese zhíxiáshì, meaning a city directly controlled by the national government.
 Beijing, formerly part of Hebei
 Tianjin, formerly part of Hebei
 Shanghai, formerly part of Jiangsu
 Chongqing, formerly part of Sichuan

Autonomous Regions 
There are 5 autonomous regions in the People's Republic of China. "Autonomous region" is the common English name for the Chinese zìzhìqū, meaning an area with greater levels of self-government to accommodate minority groups.
 Xinjiang, for the Uygurs and other Turkic peoples
 Tibet, for Tibetans
 Inner Mongolia, for Mongolians
 Guangxi, for the Zhuang
 Ningxia, for the Hui

Special Administrative Regions 
There are 2 special administrative regions in the People's Republic of China. "Special administrative region" is the common English name for the Chinese tèbié xíngzhèng qū, meaning an area under special administration as a result of treaties that returned former European colonies to Chinese control.
 Hong Kong, formerly a British colony
 Macau, formerly a Portuguese colony
List of fruits

Fruits on this list are defined as the word is used in everyday speech. It does not include vegetables, whatever their origin.  

The following items are fruits, according to the scientific definition, but are sometimes considered to be vegetables:

Food-related lists
Lists of plants
Linear algebra

Linear algebra is a branch of mathematics. It came from mathematicians trying to solve systems of linear equations. Vectors and matrices are used to solve these systems. The main objects of study currently are vector spaces and linear mappings between vector spaces. Linear algebra is useful in other branches of mathematics (e.g. differential equations and analytic geometry). It can also be applied to the real world in areas such as engineering, physics and economics.

Linear algebra describes ways to solve and manipulate (rearrange) systems of linear equations.

For example, consider the following equations:

These two equations form a system of linear equations.
It is linear because none of the variables are raised to a power.
The graph of a linear equation in two variables is a straight line.
The solution to this system is:

This is because it makes all of the original equations valid, that is, the value on the left side of the equals sign is exactly the same as the value on the right side for both equations.

Linear algebra uses a system of notation for describing system behavior, called a matrix. For the previous example, the coefficients of the equations can be stored in a coefficient matrix.

Related pages

 Matrix analysis
 Matrix function
 Numerical linear algebra
 System of linear equations

Further reading
 Israel Gelfand (1998), Lectures on linear algebra, Courier Dover Publications.
Macadamia nut

The macadamia nut is the fruit of a tree that first came from the east coast of Australia. There is 
more than one kind of Macadamia tree. Only one kind is grown for food.

The tree is an evergreen (stays green all year long). It grows up to  high. It has groups of small white flowers. It grows best in subtropical (wet and always warm) climates. It needs well-drained soil (water can flow away easily) and  of rain a year.

The nutmeat (the soft part inside the shell that can be eaten) is mostly a creamy white color. Sometimes it looks a bit yellow. It has a flavor that many people like. Macadamias are eaten roasted (cooked) by themselves. They are used in cookies, cakes, pastries, and candies. People use them like almonds and cashews as part of cooked meals. This is an Oriental style of cooking.

The first commercial orchard was started in Australia in the late 1880s. Commercial production started in Hawaii during the 1920s. Production later spread to California, Mexico, and other places with warm climate.

Macadamias are poisonous to dogs. A dog usually needs 24 to 48 hours to recover fully after eating macadamias.The plant is in the Proteaceae family of flowering plants.

References

Edible nuts and seeds
Maui

Maui is the second largest of the Hawaiian Islands, in the United States.
It has a population of just over 100,000 and is 727 square miles (1883 km²) in size. Maui is part of Maui County, Hawaii. The larger (or better known) towns include Kahului, Wailuku, Lahaina, Hana, and Wailea. Main industries are agriculture and tourism.

Maui was named for the demi-god Maui. In Hawaiian legend, he raised all the islands from the sea. Maui is also known as the "Valley Isle" for the large fertile isthmus (narrow land connection) between two volcanoes.

Geography
Maui is a volcanic doublet: an island formed from two volcanic mountains that are joined together. The older volcano, Mauna Kahalawai, is much older and has been very worn down. In common talk it is called the West Maui Mountain. The larger volcano, Haleakala, rises above 10,000 feet (3,050 m). The last eruption of Haleakala happened over 200 years ago, and this lava flow can be seen between Ahihi Bay and La Perouse Bay on the southeast shore.

Places
Other places on Maui popular with visitors include: 
Ī'ao Valley.
Haleakala crater
Road to Hāna
Wai'ānapanapa

Golf courses on Maui include:
Grand Waikapu Country Club
Ka'anapali Golf Course
Kapalua Golf Club
Makena Golf Club
Maui Country Club
Pukalani Country Club
Sandalwood Country Club
Silversword Golf Course
Wai'ehu Municipal Golf Course
Wailea Golf Club

Islands of Hawaii
Multiplication

Multiplication is an arithmetic operation for finding the product of two numbers in mathematics. It is often represented by symbols such as  and . Multiplication is the third operation in math, after addition which is the first, and subtraction which is the second. It can also be defined on non-number mathematical objects as well.

With natural numbers, multiplication gives the number of tiles in a rectangle, where one of the two numbers equals the number of tiles on one side, and the other number equals the number of tiles on the other side.

With real numbers, multiplication gives the area of a rectangle where the first number is the same as the size of one side, and the second number is the same as the size of the other side.

For example, three multiplied by five is the total of five threes added together, or the total of three fives. This can be written as 3 × 5 = 15, or spoken as "three times five equals fifteen." Mathematicians refer to the two numbers to be multiplied as "coefficients", or "multiplicand" and "multiplicator" separately (where Multiplicand × multiplicator = product).

Multiplication between numbers is said to be commutative—when the order of the numbers does not influence the value of the product. This is true for the integers (whole numbers), e.g. 4 × 6 is the same as 6 × 4, and also for the rational numbers (fractions), and for all the other real numbers (representable as a field in the continuous line), and also for complex numbers (numbers representable as a field in the plane). However, it is not true for quaternions (numbers representable as a ring in the four-dimensional space), vectors or matrices.

The definition of multiplication as repeated addition provides a way to arrive at a set-theoretic interpretation of multiplication of cardinal numbers. A more accurate representation is to think of it as scaling quantities. This animation illustrates 3 being multiplied by 2, giving 6 as a result. Notice that the blue dot in the blue segment of length 3 is placed at position 1, and the blue segment is scaled so that this dot is placed at the end of the red segment (of length 2). For multiplication by any X, the blue dot will always start at 1 and end at X. This works even if X is smaller than 1, or negative.

The opposite of multiplication is division.

Multiplication table

Teachers usually require their pupils to memorize the table of the first 9 numbers when teaching multiplication, so that more complex multiplication tasks can be performed.

Related pages
 Addition
 Division (mathematics)
 Square number
 Subtraction

References 

Arithmetics
Hyperoperations
Multiverse

A multiverse is the theory of a conjectured set of multiple possible universes, including ours, which make up reality. These universes are sometimes called parallel universes. A number of different versions have been considered.

The term "multiverse" was coined in 1895 by psychologist William James as a philosophical concept.

The cosmological multiverse 
The cosmological multiverse tries to explain why the universe we observe i.e. ''our universe'' seems so welcoming to the emergence of life. Even small changes to the way physics works would make life impossible. In a multiverse a vast number of universes are randomly created and some happen to favour life emerging there. Many inhospitable universes would also have been created, but there would be no life there to observe their existence.

The quantum multiverse 
The quantum multiverse is another version in which our universe splits into alternative futures with every quantum event. This is called many-worlds interpretation of quantum mechanics.

References 

Cosmology
Physics
Astrophysics
Universe
First language

A first language (also mother language, mother tongue, native language, arterial language, or L1) often means the language that a person learns first. It helps one understand words and concepts in the style of that language.

Sometimes, but not often, first language means the language that a person speaks best (the second language is then spoken less well than the first language, etc.). In that sense, a person could have more than one first or second language.

References

Related pages 
Soweto Uprising

Language
Mass

The mass of an object is a measure of the amount of matter in a body. A mountain has typically more mass than a rock, for instance. Mass should not be confused with the related but quite different concept of weight. 

We can measure the mass of an object if a force acts on the object. If the mass is greater, the object will have less acceleration (change in its motion). This measure of mass is called inertial mass because it measures inertia.

A large mass like the Earth will attract a small mass like a human being with enough force to keep the human being from floating away. "Mass attraction" is another word for gravity, a force that exists between all matter. When we measure the force of gravity from an object, we can find its gravitational mass. Tests of inertial and gravitational mass show that they are the same or almost the same.

Units of mass 
The unit of mass in the International System of Units is the kilogram, which is represented by the symbol 'kg'. Fractions and multiples of this basic unit include the gram (one thousandth of a kg, symbol 'g') and the tonne (one thousand kg), amongst many others.

In some fields or applications, it is convenient to use different units to simplify the discussions or writings. For instance,
 Atomic physicists deal with the tiny masses of individual atoms and measure them in atomic mass units.
 Jewelers normally work with small jewels and precious stones where masses are traditionally measured in carats, which correspond to 200 mg or 0.2 g.
 The masses of stars are very large and are sometimes expressed in units of solar masses.

Traditional units are still in encountered in some countries: imperial units such as the ounce or the pound were in widespread use within the British Empire. Some of them are still popular in the United States, which also uses units like the short ton (2,000 pounds, 907 kg) and the long ton (2,240 pounds), not to be confused with the metric tonne (1,000 kg).

Conservation of mass and relativity 

Mass is an intrinsic property of the object: it does not depend on its volume, or position in space, for instance. For a long time (at least since the works of Antoine Lavoisier in the second half of the eighteen century), it has been known that the sum of the masses of objects that interact or of the chemicals that react remain conserved throughout these processes. This remains an excellent approximation for everyday life and even most laboratory work.

However, Einstein has shown through his special theory of relativity that the mass m of an object moving at speed v with respect to an observer must be higher than the mass of the same object observed at rest m0 with respect to the observer. The applicable formula is

where c stands for the speed of light. This change in mass is only important when the speed of the object with respect to the observer becomes a large fraction of c.

References

Related pages
 Mass versus weight
 Center of mass
 Gravity
 Density
 Body mass index
 Advanced topics:
 Standard Model 
 Higgs field.

Physical quantity
Matter
Mechanics
Mac OS

For the Apple computer family, see macOS

The Macintosh Operating System (Mac OS) is a program that allows a Macintosh computer to  operate and be used. Mac OS was first made by Apple Inc. in 1984. In those days Mac OS was called Macintosh System Software – which was shortened to System or SSW (System Software). The term "Mac OS" first appeared in the splash screen for System 7.5.1, but was not adopted as the new name until the release of Mac OS 7.6.

The latest version of Mac OS is Mac OS 11 Big Sur.

Related pages
 Apple Macintosh

References 

Operating systems
MacOS
Apple Macintosh

The Apple Macintosh or just “Mac” is a line of personal computers made by the American company Apple Inc. The Macintosh was one of the first computers in which the people could use a mouse for pointing on a screen which had icons. This new way of working with a computer (interface) was known as graphical user interface. It was this feature of the Macintosh that made it so popular.

History

Processor history 
The Apple–Intel transition was when Apple changed the CPU of Macintosh computers from PowerPC processors to Intel x86 processors.  It was announced at the 2005 World Wide Developers Conference. Steve Jobs announced it.

Macintoshes were different than other personal computers for many years based on their central processor unit (CPU). At the start, Macs used Motorola 68000 chips instead of Intel chips. Later, Macs used PowerPC chips. In 2006, Macs started to use Intel chips. In 2020, Macs started to use Apple Silicon chips. Today, Macs are sold with Apple M1 chips.

Macintoshes

Software 
The Mac does not have the Windows operating system installed on it. It has its own range of operating systems, known as macOS. The newest operating system is known as “Big Sur".  Macs can run both Windows and macOS at the same time with help of a program called “Boot Camp”, which comes on every Mac.

In general, Macintosh computers cost more than other computers of the same speed.

Related pages
 iMac
 MacBook
 MacBook Air
 MacBook Pro   
 Other popular products of Apple include iPod, iPhone and iPad.

References

Computers
Macintosh
Metre

A metre (US spelling, meter) is the basic unit of length in the SI measurement system. The symbol for the metre is m. The first meaning (in the French Revolution) was one ten-millionth of the distance between the Earth's equator and the North Pole along the Paris meridian. The metre is now defined as the distance light travels in a vacuum in 1/299,792,458 of a second.

In the imperial system of measurement, one yard is 0.9144 metres (after international agreement in 1959), so a metre is very close to 39.37 inches: about 3.281 feet, or 1.0936 yards.

Units multiples

    0.000 000 000 000 000 000 000 001 Ym (yotametre) = 1 m
        0.000 000 000 000 000 000 001 Zm (zetametre) = 1 m
            0.000 000 000 000 000 001 Em (exametre) = 1 m
                0.000 000 000 000 001 Pm (petametre) = 1 m
                    0.000 000 000 001 Tm (terametre) = 1 m
                        0.000 000 001 Gm (gigametre) = 1 m
                            0.000 001 Mm (megametre) = 1 m
                                0.001 km (kilometre) = 1 m
                                 0.01 hm (hectometre) = 1 m
                                  0.1 dam(decametre) = 1 m
                                  1 m  (metre)
                                 10 dm (decimetres) = 1 m
                                100 cm (centimetres) = 1 m
                               1000 mm (millimetres) = 1 m
                          1 000 000 μm (micrometres) = 1 m
                      1 000 000 000 nm (nanometres) = 1 m
                   1 000 000 000 000 pm (picometres) = 1 m
                 1 000 000 000 000 000 fm (fermi or femtometres) = 1 m
             1 000 000 000 000 000 000 am (attometres) = 1 m
         1 000 000 000 000 000 000 000 zm (zeptometres) = 1 m
     1 000 000 000 000 000 000 000 000 ym (yoctometres) = 1 m

Related pages
Metre Convention

References
https://www.youtube.com/channel/UCLjFezysfbVZFZ_jeLB0iHg

SI units
Units of length
Molecule

A molecule is the smallest amount of a chemical substance that can exist. If a molecule were split into smaller pieces, it would be a different substance.

Molecules are made up of atoms that are stuck together in a particular shape or form. Not all combinations of atoms are equally possible; atoms make certain shapes in preference to others.  Also, they have different valency.  For example, oxygen atoms always have two bonds with other atoms, carbon atoms always have four bonds with other atoms, and nitrogen atoms always have three bonds with other atoms.

In the kinetic theory of gases, the term molecule is often used for any gaseous particle regardless of its composition. According to this definition, noble gas atoms are considered molecules as they are in fact monoatomic molecules.

In gases like air, the molecules are just flying around. In liquids like water, the molecules are stuck together but they can still move. In solids like sugar, the molecules can only vibrate.  In the fourth state of matter known as plasma, the atoms are ionized and cannot form molecules.

With a molecular formula, you can write down the numbers of all atoms in a molecule. For example, the molecular formula of glucose is C6H12O6. That means that one molecule of glucose is made up of six carbon atoms, twelve hydrogen atoms and six oxygen atoms.

Bonding 

For a molecule to exist, atoms have to stick together. This happens when two atoms share electrons. Instead of circling just one atom, the electron now circles around two. This is called a covalent bond.  Sometimes, more than one electron is shared. The more electrons are shared, the stronger the bond gets and the stronger the atoms stick together.

Bonds can also be broken apart. Since most bonds require energy to form, they also give off energy when they are broken. But before most bonds break, the molecule has to be heated. Then the atoms start to move, and when they move too much, the bond breaks. Molecules that require less energy to break than they give off when broken are called fuels. For example, a candle will just sit there and nothing happens. But when you use a match to light it, it will burn for a long time. The match brings the energy to break the first bonds, which release enough energy to break the bonds below them, until the candle has burned down.

There are also ionic bonds.

References

Other websites 
 Molecule of the Month - School of Chemistry, University of Bristol
 Antibody Molecule - The National Health Museum
 Data Book of Molecules - Home Page for Learning Environmental Chemistry

Chemistry
National anthem

A national anthem is a country's official national song that the people of a country use to remember and respect their country.

Some countries, like Spain, have a national anthem which has no lyrics (words of a song)

Note

Related pages

 List of national anthems
 National flag
Niihau

Niihau (or Niʻihau) is the smallest of the inhabited islands of Hawaii, in the United States. It has a land area of 70 sq. miles (184 km2). It is the oldest of the eight main islands.

Ownership
The whole island is owned by the Robinson family. They bought it from the Kingdom of Hawaii for $10,000. It was said that the buyer, Elizabeth Sinclair (later Sinclair-Robinson), liked the island better than other places such as Waikiki, Pearl Harbor, and the island of Lanai. There is a small US Navy base where a handful of Navy people work.

Inhabitants
The island has a few hundred permanent inhabitants. Almost all of them are native Hawaiians. They support themselves largely with small family farms. Many work for the ranch owned by the Robinsons. The native Hawaiians lead a rural, low-tech life. They speak the Hawaiian language and keep traditions alive. This is because Ms. Sinclair promised to help preserve Hawaiian culture and tradition when she bought the island. Niihau is the only one of the Hawaiian islands where the Hawaiian language is the main language.

Tourism
Niihau is also known as the "Forbidden Island". This is due to the fact that until recently, the island was off-limits to all but family members, US Navy personnel, government officials and expressly invited guests. Now, tourists can go on one of a limited number of supervised tours or hunting safaris.

Beaches
On the beaches of the island are found shells which are the only shells to be classified as gems. Niihau shells and the jewelry made from them are very popular. Many, especially those with darker and richer color, are collectors items. The sale of shells and shell jewelry brings extra money for the local people.

Islands of Hawaii
Nēnē

The Nēnē, or Hawaiian goose (Branta sandvicensis) is a species of goose. It is found today on only three Hawaiian islands. It gets its name from its soft call.

This is an unmistakable species, with its generally brown plumage (feathers) and darker head. Its strong toes have much reduced webbing (skin between the toes), an adjustment to the lava flows on which it breeds. The Nēnē goes about on land much more than other water birds. When moulting (dropping old feathers and growing new ones), the Nēnē cannot fly, as do other geese, a factor which made it vulnerable to hunting.

The Nēnē was once among the most threatened waterfowl species around the world. Once common, hunting and predators brought to the islands such as mongooses, pigs and cats reduced the population to only 30 birds in the 1950s. However, this species breeds well in captivity (zoos and bird parks), and has been successfully re-introduced. There are also good numbers in wild bird collections.

The Nēnē is the state bird of Hawaii.

References

Geese
Nature

The words nature and natural are used for all the things that are normally not made by humans. Things like weather, organisms, landforms, celestial bodies and much more are part of nature. Scientists study the way the parts of nature work. Things that have been made by people are said to be man-made or called artifacts.

There are natural sciences that study different parts of nature, for example the science of ecology is about plants and animals as a whole, while biology studies every type of living thing.

From one point of view, humans are a prime example of nature, and are the most widely studied natural inhabitants of the planet earth. Humans interact with each other in their natural environment on a day-to-day basis. Every part of nature  everything from the air outside to the dirt on the ground  is interdependent. Medicine studies humans in health and sickness. 

From another point of view, humans and nature can be said to be in conflict. Nature is often seen by humans as natural resources. People cut down trees, mine ores, and grow crops. Fires, cars, and factories make a lot of smoke and harm many places. People who like to leave nature unharmed and those who feel they need to use more of nature often fight about what they should do. In the modern world, with many more people and many big cities, these problems are becoming more serious.

Nature, in the broadest sense, means the physical world as a whole. This is the meaning that physics, the study of nature (etymologically), takes.

A useful definition of natural is 
"Happening or operating in accordance with the ordinary course of nature". Oxford Shorter English Dictionary says the word in this sense is first found in 1477.

Related pages 
 Human timeline
 Life timeline
 Nature timeline
Nature versus nurture

Other websites

References 

 
Bionics
Negentropy

Negentropy is reverse entropy. It means things becoming more in order. By 'order' is meant organisation, structure and function: the opposite of randomness or chaos. One example of negentropy is a star system such as the Solar System. Another example is life. 

As a general rule, everything in the universe tends towards entropy. Star systems eventually become dead. All energy has gone, and everything in the system is at the temperature of the surrounding space. The opposite of entropy is negentropy. It is a temporary condition in which certain things are hotter and more highly organised than the surrounding space. This is the second law of thermodynamics:
The second law of thermodynamics states that the total entropy of an isolated system always increases over time.

Life is considered to be negentropic because it converts things which have less order, such as food, into things with more order, such as cells in the body, tissues, and organs. In doing so, it gives off heat.  Another example of negentropic things are societies, or social systems, because they take disorderly things such as communications, and make them more orderly and useful.

Notes 

Thermodynamics
North America

North America is a large continent in the Northern and Western Hemispheres of Earth. It is to the east of the Pacific Ocean, the west of the Atlantic Ocean, the south of the Arctic Ocean, and it is the northern part of the Americas. The southernmost part is Central America. It is the third largest continent in the world, after Asia and Africa. North America has a population of around 371 million and is the 4th most populous continent in the world. 

Hundreds of millions of years ago, North America was part of a larger ancient supercontinent named Laurasia. A few million years ago, a new land bridge arose and connected North America to South America. Beringia connected North America to Siberia a few times during ice ages in the past 20,000 years. North America has many warm tropical islands such as the Bahamas. North America is currently north of South America.

Countries

Related pages
 Central America
 South America

 
Laurasia
1 (number)

One (1) is the first natural number, followed by two.
It represents a single item.
A human typically has one head, nose, mouth, and navel (belly-button).
The Roman numeral for one is I.

Mathematics 
In mathematics, 1 is the multiplicative identity. It is sometimes called the "unity". It is also the only number for which these special facts are true:
 Any number  multiplied by 1 equals that number: . For example, .
 Any number  divided by 1 equals that number: . For example, .
 Any number , other than 0, divided by itself always equals 1: . For example: .
 1 cannot be divided by any other number bigger than itself so that the result is a natural number.

In mathematics, 0.999... is a repeating decimal that is equal to 1. Many proofs have been made to show this is correct.

Computer science 
The number one is important for computer science, because the binary numeral system uses only 1s and 0s to represent numbers. In machine code and many programming languages, one means "true" (or "yes") and zero means "false" (or "no").

Other meanings 
 In Germany and Austria, one is the grade for "very good". It is the best grade of six possible grades in Germany, and the best of five possible grades in Austria. In the Netherlands, one is the lowest grade, and ten the highest. In Poland, one is also the lowest grade, but the highest is six.
 In numerology, the number one is a symbol for everything (unity), the beginning, and God.

Related pages 

 Zero
Mathematical constant

References 

Integers
Natural numbers
Square numbers
O Canada

O Canada is the national anthem of Canada. 

Calixa Lavallée wrote the music; Adolphe-Basile Routhier wrote the words in French. It was first sung in French in 1880. Robert Stanley Weir wrote English words for the song in 1908.

It was sung as the national anthem for many years before the government made it official on 1 July (Canada Day) in 1980. 

Here are the words, explained in Simple English:

 O Canada! Our home and native land, 
 True patriot love in all of us command! 
 With glowing hearts we see thee rise 
 The True North strong and free, 
 From far and wide, O Canada, 
 We stand on guard for thee. 
 God keep our land glorious and free! 
 O Canada, we stand on guard for thee; 
 O Canada, we stand on guard for thee.

("Canada, our home and the country where we were born, everything we do is for you! With joy we watch you get better and better. You are the True North, strong and free. Our citizens come from all over the earth and we watch over you to keep you safe. God, please keep our land good and free! O Canada, we watch over you to keep you safe.")

Here are the words in French. The words in French and English do not mean the same thing.

 Ô Canada! Terre de nos aïeux, 
 Ton front est ceint de fleurons glorieux! 
 Car ton bras sait porter l'épée, 
 Il sait porter la croix! 
 Ton histoire est une épopée 
 Des plus brillants exploits. 
 Et ta valeur de foi trempée 
 Protégera nos foyers et nos droits; 
 Protégera nos foyers et nos droits. 

("Canada, land of our parents and grandparents, you wear a crown of beautiful flowers! You can carry a sword, and you can carry a cross (for Christianity); your whole history is full of the great things you have done. You are brave and faithful, and this will protect our homes and our rights.")

References

Canada
National anthems
Open content

Open content is when someone creates something and lets others copy it or change it without having to ask for permission. Any media can be open content, from text and pictures to video and sound.

When someone creates something (like a picture or book), they can make that work "open".  This means that other people are allowed to copy it and change it if they want.  Something that is open content may be free of charge, but it does not have to be. 

The Simple English Wikipedia is open content. So are other Wikipedias. If a person changes open content or makes new open content, everyone can give it to anyone else, or even sell it. It is never needed to ask permission to do this, because the people who wrote the text already gave their permission when they clicked the "save" button.

License 

The rules that say how people can use, change and pass around open content are called a license. A license explains exactly what you are allowed to do with the content that falls under it. Licenses are often written in difficult language (legal jargon), but many licenses have summaries that are much easier to understand.

The makers of open content get to choose what license to use for their work, and everyone else has to follow it. Only the maker, who owns the copyright, can change it to another license.  Most open content licenses say that when others change the work, they must also declare it to be open and under the same license.  This is called share-alike and means that anything based on work will always be open content.

All the content in Wikipedia is open under the rules of the Creative Commons Attribution/Share-Alike License, a very well-known open content license. Another well-known open content license is the GNU Free Documentation License.

Related pages   
 Free software
 Author
 Open source
 Content license

References 

Software
Art
Free content