the-french-artist/wikipedia_20220301.simple_sentence_split huggingface dataset:
There is a slight difference in the mass of the resulting krypton and barium, and the mass of the original uranium, but the energy that is released by the change is huge.
One way to express this idea is to write Einstein's equation as:
E = (muranium – mkrypton and barium) c2
The c2 in the equation stands for the speed of light squared.
To square something means to multiply it by itself, so if you were to square the speed of light, it would be 299,792,458 meters per second, times 299,792,458 meters per second, which is approximately
(3•108)2 =
(9•1016 meters2)/seconds2=
90,000,000,000,000,000 meters2/seconds2
E = 1 kg • 90,000,000,000,000,000 meters2/seconds2
E = 90,000,000,000,000,000 kg meters2/seconds2
About 60 terajoules were released by the atomic bomb that exploded over Hiroshima.
So about two-thirds of a gram of the radioactive mass in that atomic bomb must have been lost (changed into energy), when the uranium changed into krypton and barium.
The idea of a Bose-Einstein condensate came out of a collaboration between S. N. Bose and Prof. Einstein.
Einstein himself did not invent it but, instead, refined the idea and helped it become popular.
Momentum, mass, and energy
p represents momentum
m represents mass
v represents velocity (speed)
When Einstein generalized classical physics to include the increase of mass due to the velocity of the moving matter, he arrived at an equation that predicted energy to be made of two components.
One component involves "rest mass" and the other component involves momentum, but momentum is not defined in the classical way.
The equation typically has values greater than zero for both components:
E2 = (m0c2)2 + (pc)2
E represents the energy of a particle
m0 represents the mass of the particle when it is not moving
p represents the momentum of the particle when it is moving
c represents the speed of light.
A photon has no rest mass, but it has momentum. (
Light reflecting from a mirror pushes the mirror with a force that can be measured.)
In the case of a photon, because its m0 = 0, then:
E2 = 0 + (pc)2
E = pc
p = E/c
The energy of a photon can be computed from its frequency ν or wavelength λ.
These are related to each other by Planck's relation, E = hν = hc/λ, where h is the Planck constant (6.626×10−34 joule-seconds).
Knowing either frequency or wavelength, you can compute the photon's momentum.
E02 = (m0c2)2 + 0
E0 = m0c2
Therefore, the quantity "m0" used in Einstein's equation is sometimes called the "rest mass." (
The "0" reminds us that we are talking about the energy and mass when the speed is 0.)
This famous "mass-energy relation" formula (usually written without the "0"s) suggests that mass has a large amount of energy, so maybe we could convert some mass to a more useful form of energy.
The nuclear power industry is based on that idea.
mv2 = m02 / (1 – v2/c2)
In this case, we can say that E = mc2 is also true for moving particles.
The General Theory of Relativity
The General Theory of Relativity was published in 1915, ten years after the special theory of relativity was created.
Einstein's general theory of relativity uses the idea of spacetime.
Spacetime is the fact that we have a four-dimensional universe, having three spatial (space) dimensions and one temporal (time) dimension.
Any physical event happens at some place inside these three space dimensions, and at some moment in time.
According to the general theory of relativity, any mass causes spacetime to curve, and any other mass follows these curves.
Bigger mass causes more curving.
This was a new way to explain gravitation (gravity).
General relativity explains gravitational lensing, which is light bending when it comes near a massive object.
This explanation was proven correct during a solar eclipse, when the sun's bending of starlight from distant stars could be measured because of the darkness of the eclipse.
General relativity also set the stage for cosmology (theories of the structure of our universe at large distances and over long times).
Einstein thought that the universe may curve a little bit in both space and time, so that the universe always had existed and always will exist, and so that if an object moved through the universe without bumping into anything, it would return to its starting place, from the other direction, after a very long time.
He even changed his equations to include a "cosmological constant," in order to allow a mathematical model of an unchanging universe.
The general theory of relativity also allows the universe to spread out (grow larger and less dense) forever, and most scientists think that astronomy has proved that this is what happens.
When Einstein realized that good models of the universe were possible even without the cosmological constant, he called his use of the cosmological constant his "biggest blunder," and that constant is often left out of the theory.
However, many scientists now believe that the cosmological constant is needed to fit in all that we now know about the universe.
A popular theory of cosmology is called the Big Bang.
According to the Big Bang theory, the universe was formed 15 billion years ago, in what is called a "gravitational singularity".
This singularity was small, dense, and very hot.
According to this theory, all of the matter that we know today came out of this point.
Einstein himself did not have the idea of a "black hole", but later scientists used this name for an object in the universe that bends spacetime so much that not even light can escape it.
They think that these ultra-dense objects are formed when giant stars, at least three times the size of our sun, die.
This event can follow what is called a supernova.
The formation of black holes may be a major source of gravitational waves, so the search for proof of gravitational waves has become an important scientific pursuit.
Beliefs
Many scientists only care about their work, but Einstein also spoke and wrote often about politics and world peace.
He liked the ideas of socialism and of having only one government for the whole world.
He also worked for Zionism, the effort to try to create the new country of Israel.
Prompted by his colleague L. E. J. Brouwer, Einstein read the philosopher Eric Gutkind's book Choose Life, a discussion of the relationship between Jewish revelation and the modern world.
On January 3, 1954, Einstein sent the following reply to Gutkind: "The word God is for me nothing more than the expression and product of human weaknesses, the Bible a collection of honourable, but still primitive legends which are nevertheless pretty childish. ....
For me the Jewish religion like all other religions is an incarnation of the most childish superstitions."
In 2018 his letter to Gutkind was sold for $2.9 million.
Even though Einstein thought of many ideas that helped scientists understand the world much better, he disagreed with some scientific theories that other scientists liked.
The theory of quantum mechanics discusses things that can happen only with certain probabilities, which cannot be predicted with more precision no matter how much information we might have.
This theoretical pursuit is different from statistical mechanics, in which Einstein did important work.
Einstein did not like the part of quantum theory that denied anything more than the probability that something would be found to be true of something when it was actually measured; he thought that it should be possible to predict anything, if we had the correct theory and enough information.
He once said, "I do not believe that God plays dice with the Universe."
Because Einstein helped science so much, his name is now used for several different things.
A unit used in photochemistry was named for him.
It is equal to Avogadro's number multiplied by the energy of one photon of light.
The chemical element Einsteinium is named after the scientist as well.
In slang, we sometimes call a very smart person an "Einstein."
Most scientists think that Einstein's theories of special and general relativity work very well, and they use those ideas and formulas in their own work.
Einstein disagreed that phenomena in quantum mechanics can happen out of pure chance.
He believed that all natural phenomena have explanations that do not include pure chance.
He spent much of his later life trying to find a "unified field theory" that would include his general relativity theory, Maxwell's theory of electromagnetism, and perhaps a better quantum theory.
Most scientists do not think that he succeeded in that attempt.
Einstein, Albert and Infeld, Leopold 1938.
The evolution of physics: from early concept to relativity and quanta.
A non-mathematical account.
What Did Albert Einstein Invent?
1879 births
1955 deaths
Cardiovascular disease deaths in the United States
Deaths from aortic aneurysm
German Nobel Prize winners
German physicists
Jewish academics
Jewish American academics
Jewish American scientists
Jewish German academics
Jewish German scientists
Jewish Nobel Prize winners
Naturalized citizens of the United States
Nobel Prize in Physics winners
People from Ulm
Refugees from Nazism
Swiss Jews
Swiss scientists
American theoretical physicists
Educators from New Jersey
Euro is the currency (money) of the countries in the eurozone.
One euro is divided into 100 cent (officially) (singular) or "cents" (unofficially).
It was created in 1999, but until 1 January 2002 it was used only for electronic payments.
In 2002, 12 countries of the European Union (EU) took their state currencies out of circulation and adopted euro notes and coins as their only money.
There was a change-over period, called the "transition period", when both the old national money and the euro were accepted, but by 28 February 2002, all 12 countries were using just euros.
In 2006, Slovenia became the 13th country to use the euro.
In 2008 Cyprus and Malta became the 14th and 15th countries to use the euro.
In 2009, Slovakia became the 16th country to use the euro.
In 2011, Estonia became the 17th country to use the euro.
In 2014, Latvia became the 18th country and in 2015, Lithuania became the 19th country to use the euro.
On every banknote, there is a picture of a different European building style.
All banknotes are the same throughout the entire eurozone; there are no different designs for different countries, unlike the euro coins.
One side of each coin is the same in all euro countries.
The other side is different since each country who mints the coins inserts a symbol relating to that country.
Today there are many different sets of coins.
Any of the coins can be used everywhere throughout the eurozone despite the country-specific symbol on the back.
The ten new European countries that entered the European Union in May 2004 are planning to adopt the Euro also.
First they must meet some conditions to show that they have stable economies.
It is also legal to simply write euro.
This is especially useful when the symbol cannot be produced, or the result is not satisfactory.
Andorra 1)
Monaco 1)
San Marino 1)
Vatican City 1)
Kosovo 2)
Montenegro 2)
1) this countries print own mints
2) this countries use the euro unofficial
Cape Verdean escudo
Comoros franc
Central African CFA franc
West African CFA franc
France's Pacific territories CFP Franc
Bosnia-Herzegovinan convertible mark
Bulgarian lev
Hungary forint
Denmark krone
Euro Coins and Notes
The EURO banknotes - pictures and history
Currency of Europe
Certain currencies are said to be "pegged" or "fixed" to something, usually another currency.
A fixed or pegged currency is one that has a constant value compared to what it is pegged to.
For example, the Cape Verdian escudo is pegged to the Euro.
If the value of the Euro goes up 1% compared to another form of currency, the value of the escudo also goes up 1% compared to that same currency.
Many countries have used systems where their currency was pegged to a commodity rather than to another currency.
Most used either gold or silver.
When they did this, as the value of gold increased, so did the value of their money.
This was called the "gold standard" or "silver standard".
Most countries stopped using silver and gold standards in the 20th century.
the United States dollar
the Euro
the British pound
Names of different currencies around the world
Afghani - Afghanistan
Baht - Thailand
Balboa - Panama (U.S. dollar used for paper money)
Birr - Ethiopia
Bolívar - Venezuela
Boliviano - Bolivia
Cedi - Ghana
Colón - Costa Rica
Cordoba - Nicaragua
Crown - Czech Republic (koruna), Denmark (krone), Estonia (kroon), Iceland (króna), Norway (krone), Sweden (krona).
See also: British Crown (coin)
Dalasi - The Gambia
Dinar - Algeria, Bahrain, Iraq, Jordan, Kuwait, Serbia, Tunisia
Denar - North Macedonia
Dirham - Morocco, United Arab Emirates, Libya, Qatar, Jordan
Dollar - Many countries, including the United States, Canada, Australia, New Zealand, Hong Kong, and others
Dong - Vietnam
Drachma - (Greece--now uses euro)
Dram - Armenia
Escudo - Cape Verde, (Portugal--now uses euro)
European Union (as an organisation; the euro is not legal tender in every EU country.)
EU members: Austria, Belgium, Estonia, Finland, France (except Pacific territories using CFP Franc), Germany, Greece, Ireland, Italy, Latvia, Lithuania, Luxembourg, Netherlands, Portugal, Slovakia, Spain.
Countries that have made legal agreements with the EU to use the euro: Andorra, Monaco, San Marino, Vatican City.
Countries that unilaterally use the euro: Montenegro and Kosovo.
Currencies pegged to the euro: Cape Verdian escudo, CFA franc, CFP Franc, Comoran francs, Bulgarian lev, Danish krone, the convertible marka of Bosnia and Herzegovina
Forint - Hungary
Franc
Swiss franc - Switzerland, Liechtenstein.
CFA franc - Benin, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Côte d'Ivoire, Democratic Republic of the Congo, Equatorial Guinea, Gabon, Guinea, Guinea-Bissau, Republic of the Congo,
CFP Franc - France's Pacific territories of New Caledonia, French Polynesia, Wallis and Futuna.
Comoran francs - Comoros (pegged to the French franc, then the euro).
Djiboutian franc - Djibouti (pegged to the US dollar since 1973).
Formerly using Begian-luxembourgish franc - Belgium, Luxembourg.
Formerly using French franc: Andorra, Monaco, France (including: French Guiana, Guadeloupe, Martinique and La Réunion, Saint Pierre and Miquelon and Mayotte).
Gourde - Haiti
Guilder - Aruba, Netherlands Antilles (Netherlands--now uses euro)
Iranian real - Iran
Kina - Papua New Guinea
Koruna - Czech Republic (Slovakia now uses euro)
Kroon - Estonia
Krona - Iceland, Sweden
Krone - Denmark, Faroe Islands, Greenland, Norway
Kuna - Croatia
Kwacha - Zambia and Malawi
Kwanza - Angola
Kyat - Burma
Lari - Georgia
Lats - Latvia
Lek - Albania
Lempira - Honduras
Leone - Sierra Leone
Leu - Romania, Moldova
Lev - Bulgaria
Lira - (Cyprus, Italy, San Marino, Vatican City--now use euro)
Turkish lira - Turkey
Litas - Lithuania
Manat
Azerbaijani manat - Azerbaijan
Turkmen manat - Turkmenistan
Mark - (Germany-- now uses euro)
Marka - Bosnia and Herzegovina
Markka - (Finland now uses euro)
Nakfa - Eritrea
Namibian dollars - Namibia
Ngultrum - Bhutan
Pataca - Macau
Peseta - (Andorra, Spain--now use euro)
Peso - Argentina, Chile, Colombia, Cuba, Dominican Republic (Dominican peso, Mexico, Philippines, Uruguay
Pound - Cyprus, Egypt, Falkland Islands, Gibraltar, Guernsey, Jersey, United Kingdom (Ireland--now uses euro)
Pula - Botswana
Quetzal - Guatemala
Rand - South Africa
Real - Brazil
Renminbi - People's Republic of China
Riel - Cambodia
Ringgit - Malaysia
Riyal - Saudi Arabia
Rouble - Belarus, Russia
Rufiyah - Maldives
Rupee - Republic of India, Mauritius, Nepal, Pakistan, Seychelles, Sri Lanka
Rupiah - Indonesia
Schilling - (Austria--now uses euro)
Shekel - Israel, Gaza Strip, West Bank
Shilling - Kenya
Sol - Peru
Som - Kyrgyzstan
Sucre - Ecuador
Taka - Bangladesh
Tenge - Kazakhstan
Tolar - Slovenia
Toman - Iran
Vietnam ~ Dong (DVN)
Won - North Korea, South Korea
Yen - Japan
Yuan - People's Republic of China
Zloty - Poland
MERCURE, an atmospheric dispersion modeling CFD code developed by Électricité de France
Mercure Hotels, a chain of hotels run by Accor
French ship Mercure (1783)
Dassault Mercure, a French airliner built in the 1970s
A radio telescope is a type of antenna used for radio astronomy.
The majority look like a huge satellite television dish.
Stars shine, and the light can be seen with an ordinary telescope, but they also give off radio waves.
Scientists with radio telescopes receive these radio waves and use computers to learn about the stars.
Other things like black holes also give off radio waves, and radio telescopes are useful for learning about them too.
The dish is sometimes constructed of a conductive wire mesh whose openings are smaller than a wavelength.
The information received by several radio telescopes in different places can be combined.
This gives similar results to having a single dish as big as the distance between the telescopes.
It can receive very faint signals, and see more details.
The biggest telescope is a virtual radio telescope almost as big as the Earth, called the Event Horizon Telescope.
A light year (symbol: ly)  is the distance that light travels in empty space in one year.
Since the speed of light is about 300,000 km per second (about 186,000 miles per second), then a light year is about 10 trillion kilometers (about 6 trillion miles).
A light year is not a length of time.
The light year is used in astronomy because the universe is huge.
Space objects such as stars and galaxies may be hundreds, thousands or millions of light years away.
Think of a star at a distance of 100 light years from us on Earth.
Light leaves the star and takes 100 years to get to us.
When we see the star's light, we are seeing that star as it was 100 years ago.
Similar distance measurements
Light minute - The distance that light travels in one minute (about 18,000,000 km per minute, or 11,160,000 miles per minute).
For example, our Sun is about 8 light minutes from Earth
Light second - The distance that light travels in one second (about 300,000 km per second, or 186,000 miles per second)
For example, our Moon is about 1¼ light seconds from Earth
Astronomical distances
Korea is a peninsula in northeast Asia.
It covers a peninsula called the Korean Peninsula.
Korea became a country (or state) in 918.
In 1948, it split into two countries: North Korea and South Korea.
North and South Korea and their allies fought against each other in the Korean War.
People have lived in Korea for about 15,000 years.
In the past, some of modern Manchuria and Siberia was governed by Korea.
Korea is known for its fine silk.
In the 7th century, the people of China sought after gold-workers from Korea.
Europeans had little knowledge about Korea until the modern era.
Korea is famous for its traditional food kimchi.
The Korean people usually eat sticky white rice.
Traditionally, Koreans eat seaweed soup on their birthdays.
People believe the soup is also good for pregnant women.
South Korea has over 50 million people, and North Korea has more than 23 million.
South Korea's biggest city is Seoul, the capital of South Korea.
The city has more than 10 million people and the region of Seoul has more than 15 million people.
North Korea's biggest city is Pyongyang, the capital of North Korea.
It has fewer than 4 million people.
Korean people speak the Korean language.
Many people in South Korea study English and other languages such as Chinese, Japanese, ... in school.
In the Korean language Korea  is  known as 조선 in North Korea and 한국 in South Korea
South Korea is an advanced country with large cities, high-speed rail trains, high-speed internet, and many television and radio networks.
Many Korean television dramas are popular around the world.
But there are still poor areas, even in South Korea.
The Korean farmers are not rich and struggle to compete with cheap food from other countries.
Gojoseon is the first state in Korean history.
It was established in 2333 BCE.
Its real name is Joseon, but it is called Gochosun to make it different from other Joseon in Korean history.
Go is a Korean prefix meaning 'old'.
The founder of Gojoseon is said to be Dangun.
The Korean people believe that Dangun established the country on October 3rd, and still celebrate that day.
In Korea, October 3rd is a national holiday, which is named Gaecheonjeol (The day heaven opened).
It is said to be the day that Dangun's father whose name is Hwan-ung came from the sky on October 3rd 2457 BCE.
Gochosun was destroyed by the Chinese Han Dynasty in 108 BCE.
After Gojoseon had been destroyed, there were many confederations in the Korean Peninsula and Manchuria: Mahan, Byeonhan, Jinhan, Buyeo, Dongye, Okjeo, Goguryeo, and so on.
The ancient confederation countries later merged into three more powerful kingdoms and an advanced confederation country.
Between 57 BC and the year 668 there were three kingdoms in the Korean Peninsula and Manchuria.
The names of the kingdoms were: Silla, Goguryeo and Baekje.
In the year 372, the religion Buddhism came from China to Korea.
Buddhism was very important in Korea.
In the year 660, the kingdom of Silla invaded the kingdom of Baekje.
In the year 668 the kingdom of Silla invaded the kingdom of Goguryeo.
The people of Goguryeo ran away and made a new kingdom with the name Barhae.
After a little time, the kingdom of Balhae was invaded by Liao Dynasty.
When Silla was the only country, it had the name Unified Silla.
In the Silla kingdom Buddhism was very important.
The northern and southern kingdoms
In the year 698, Balhae was founded by allies of Goguryeo.
We call the time when united Silla and Balhae were existing together (698∼926) The northern and southern kingdoms period.
Goryeo (Korea)
In the year 918 the kingdom of Goryeo began.
The name Korea comes from Goryeo.
The kingdom of Goryeo had power until the year 1392.
The kingdom of Goryeo wrote the law in books, and had a big government.
Buddhism was very important in the kingdom of Goryeo.
Bronze-type printing technology was invented in Goryeo Dynasty.
This is known as the world's oldest bronze-type printing technology.
The Mongol empire conquered Goryeo and forced Korea to pay a tribute in Korean girls and eunuchs to the Mongol court with about 500,000 Korean girls and eunuchs taken to Yuan China.
Mongol and Central Asian Semu Hui Tammachi army officials in Korea itself also took Korean women as concubines and Korea officials complained about it, begging the Mongol court to withdraw them from Korea.
Koreans wrote erotic songs about how Korean women were seduced by Central Asian Muslims in their bakeries.
An amusing incident is reported as having occurred about this time.
A courtier named Pa-gyu observed to the king, “The male population of the country has been decimated but there are still plenty of women.
For this reason it is that the Mongols take so many of them.
There is danger that the pure Koryŭ stock will become vitiated by the intermixture of wild blood.
The king should let each man take several wives and should remove the restrictions under which the sons of concubines labor."
When the news of this came to the ears of the women they were up in arms, as least the married portion ; and each one read to her spouse such a lecture that the subject was soon dropped as being too warm to handle.
When the king passed through the streets with Pa-gyu in his retinue the women would point to the latter and say “There goes the man who would make concubines of us all."
A courtier named Pa Gyu observed to the king: “The male population of the peninsula has been decimated but there are still plenty of women.
This is why the Mongols take so many of them.
There is danger that the pure Koryo stock will become vitiated by the admixture of the wilt stock.
The king should let each man take several wives and should remove the disabilities under which the sons of concubines at present labor.”
When this came to the ears of the women they were up in arms and each one read her lord such a lecture that the matter was dropped as being too hot to handle.
When the king passel through the streets with Pa Gyu in his retinue, the women would point to him and say, “There goes the man who would wake concubines of us all."
A Korean woman was married off to the Arab (Omani or Yemeni HAdrami) Sayyid bin Abu Ali by Kublai Khan in 1292 when he came to the Yuan Mongol court in Beijing.
His grave was in Quanzhou after he died in Beijing in 1299.
The Tibetan Sangha was the Korean woman's previous husband and her father was Ch'ai In'gyu Korean wives were taken in Korea itself by Yuan officials and diplomats there and Korean women were sent to Yuan officials and ministers and the emperor in China and Korean noble women were sent as wives to Mongol aristocrats and elite as well as Mongol soldiers and Southern Song Han Chinese soldiers who defected to the Mongol Yuan.
The Hui historian Ma Juan wrote about Korean women marrying Indian, Uyghur and Turkic Semuren men during the Yuan dynasty.
In the year 1392 a man from the military of Korea went to China.
His name was Sejo(Yi Seonggye).
Sejo's job was to attack China.
But Sejo returned without doing it.
When Sejo came back to Korea, he changed the kingdom.
Sejo became king.
The name of the kingdom was Joseon.
In the year 1394, the people of Joseon moved the capital to Seoul.
The religion of Buddhism was not important.
A new religion, Confucianism was important.
Confucianism came from China.
In the year 1443 the king Sejong ruled.
He invented the Korean alphabet Hangeul.
In the year 1592 and the year 1598 the people from Japan fought Korea.
A man from the military made very strong ships, including the famous turtle ship.
The name of the man was Yi Sun-sin.
With the strong ships, the people of Korea won.
In the 19th century the people of Korea did not want to trade with other people.
People called Korea Hermit Kingdom.
The people of the United States and Japan wanted to trade with Korea.
Before 1876, people failed when they tried to use force to trade with Korea.
In the year 1876 the military of Japan fought Korea.
Korea and Japan made a contract to trade.
In 1895 Japan won the First Sino-Japanese War in the Korean peninsula.
This ended Chinese influence in Korea.
Empress Myeongseong, also called Queen Min, wanted the Russian Empire as a friend, to help Korea against Japan.
Agents of the Ambassador of Japan killed her in October 1895.
In 1905 Japan won the Russo-Japanese War.
In the year 1910, the emperor of Japan made Korea a colony of Japan.
Colony of Japan to today
When World War II started, the policy of the Japanese government changed.
The government made the religion of Japan (Shinto) the religion of Korea.
In 1945 Japan lost World War II.
The United States and Soviet Union made a contract.
United States occupied the south of Korea and Soviet Union occupied the north of Korea.
The people of Korea wanted to be independent.
The United States and the Soviet Union agreed the people of Korea would be free and independent.
But soon the United States and Soviet Union were not friends and the Cold War started.
United States and Soviet Union refused to settle a deal.
In 1948 the people in the south made an independent country called South Korea (also called the Republic of Korea).
The United States helped them.
In 1948 the people in the north also made a country North Korea (also called the DPRK or Democratic People's Republic of Korea).
The Soviet Union helped North Korea.
In 1950 a war started in Korea.
The name of the war was the Korean War.
The war ended in 1953, but no peace treaty was signed.
The border line between North and South was almost the same in the end as it was before the war.
918 establishments
1948 disestablishments in Asia
10th-century establishments in Asia
ESL, which means "English as a Second Language".
This is most often used in a country where English is the primary language
EFL, which means "English as a Foreign Language".
This is most often used in a country where English is not the primary language
EAL, which means "English as an Additional Language".
This is rarely used.
ESOL, which means "English for Speakers of Other Languages".
ELF, which means "English as a Lingua Franca", a term relating to Globalization.
Each of these acronyms means roughly the same thing.
In each, the learners already have another native or "mother" language, and they want to learn English as well.
The teaching of English as a second language has a long history.
For example, the official introduction of English into India's education system began in 1835.
English as a second language is the single most popular subject in the world, after mathematics.
English is a very important language in business.
Many people study English as a foreign language, because they want a better job.
English is also very important in education.
Many pages on the internet are in English.
Many people study English in a country where the people speak English.
This way, many students learn to listen and speak English better.
There are many English exams.
These English exams are important for learners.
They may show how well a person can use English.
It is very difficult to compare different English exams.
Every exam is a little different.
Read Testing English as a foreign language for more information.
Global Scale of English
Global Scale of English (GSE) is a test for learners of English as a second or foreign language.
The GSE is a list of can-do statements based on the Common European Framework of Reference (CEFR) for English.
Learners' abilities are rated on a 10-to-90 point scale for each of the four basic skills (speaking, listening, reading, and writing).
A learner reaches a level on the scale when she or he can correctly perform 50% of the can-do tasks at that level.
The education company Pearson PLC developed the scale.
Teaching English as a foreign language (TEFL) is referred to the practice of teaching the English language to the students with different first languages.
It is taught in the state school system or privately with a language school or with a tutor.
TEFL can also take place in an English-speaking country for people who have immigrated there.
TEFL teachers may be native or non-native speakers of English.
Other forms of TEFL are TESL (Teaching English as a second language), TESOL (Teaching English to speakers of other languages), and ESL (English as a second language).
Additional types of TEFL certification include: CTBE (Certificate in Teaching Business English), CTYL (Certificate in Teaching Young Learners), CTO (Certificate in Teaching Online).
Switzerland (; ; ; ; Swiss German: Schwiz) is a comparatively small country in Western Europe.
The official name of Switzerland is Confoederatio Helvetica.
This is Latin and is not often used except for state documents.
Switzerland is a confederation of even smaller states, which are the 26 cantons.
Switzerland is known for its neutrality.
A country is neutral when it does not take sides among the countries who are at war.
Switzerland has been neutral since 1815.
Many international organizations are in Switzerland.
The United Nations has a main office (but not its headquarters) in Geneva.
Its predecessor organization, the League of Nations, was headquartered in Geneva.
There are four official languages in Switzerland: German, French, Italian, and Romansh.
Some cantons and even towns have two languages spoken in them, and the largest canton by area, Graubünden, has three.
About 2/3 of the population speak German; French is spoken in the west of the country, while Italian is spoken in the canton of Ticino and Romansh in parts of Graubünden.
Romansh language is spoken less than by 1% of the population.
The defacto capital of Switzerland is Bern.
The largest city of Switzerland is Zürich.
To the north of Switzerland is Germany.
East of Switzerland are Austria and Liechtenstein.
To the south of Switzerland is Italy.
To the west of Switzerland is France.
The area of Switzerland is 41,285 km².
The confederation is divided into 23 full states called cantons.
All 26 cantons are: Aargau, Appenzell Innerrhoden, Appenzell Ausserrhoden, Basel-Stadt, Basel-Land, Berne, Fribourg, Geneva, Glarus, Graubünden,  Jura, Lucerne, Neuchâtel, Nidwalden, Obwalden, Schaffhausen, Schwyz, Solothurn, St. Gallen, Thurgau, Ticino, Uri, Valais, Vaud, Zug, and Zürich.
The mountains are very tall in the center and south of Switzerland.
About 60% of Switzerland is in the Alps area.
Only few people live here.
The highest mountain is the Dufour Peak at 4,634 m.
Many of the mountains have ice all year.
This ice is called glaciers.
The rivers Rhine, Rhône, and many other rivers start in the mountains of Switzerland.
There are many lakes in Switzerland.
The biggest lakes are all in the north and west: Lake Geneva (Lac Léman), Lake Zürich, Lake Neuchâtel and Lake Constance (Bodensee).
Mountains in the north of Switzerland are fewer and smaller.
That is why most Swiss people live in cities and towns in the north.
The Jura mountains are in the northwest of Switzerland.
There are about 8.4 million people in Switzerland.
About 64% of the people speak Swiss German (German Alemannic) as their first language, in northern and central Switzerland.
19% of the people speak French as their first language, mainly in the west of Switzerland.
8% of the people speak Italian, in the south of Switzerland.
Only 1% of the people speak Romansh, in the southeastern part of Switzerland.
Romansh is an old language that is similar to Latin.
The German-speaking people of Switzerland do not actually speak "German" as their native language.
Swiss people speak something called Alemannic which has its own writing language and grammar but still is normally considered a German dialect.
Alemannic may be difficult for Germans to understand.
Swiss people do write like the people from Germany and also speak standard German very well, especially in the larger cities.
About 23% of the people in Switzerland do not come from Switzerland.
They come from other places to usually work in Switzerland.
The religion of most people in Switzerland is Christianity.
43% of the population follow Catholicism.
35% of the population follow Protestantism.
2% follow Eastern Orthodoxy.
The religion of 4% of the population is Islam.
The rest follow other religions, or they have no religion.
In 1291, people from Uri, Schwyz and Unterwalden wanted to be free.
They signed a contract to work together called the Eternal Alliance.
Together, they could be free from the people of Habsburg, who were very strong.
In 1315 the people from the Eternal Alliance fought the Habsburgs in battles at Morgarten, Sempach and Näfels.
The people of the Eternal Alliance won all the battles.
People from other areas signed the contract and joined the Eternal Alliance.
More and more people worked together to be free.
In 1648, other countries from Europe made an agreement that Switzerland was free.
The name of this agreement was the Peace of Westphalia.
More areas came to be part of Switzerland.
Switzerland was important to the slave trade that forced black Africans to be sold as slaves.
Swiss companies made indiennes, which are a kind of cloth.
These cloths were sent to Africa and exchanged for captured slaves.
Some Swiss also joined French companies already making indiennes or owned plantations with slaves in French colonies.
In 1798, France invaded Switzerland.
The ruler of France was Napoleon.
He changed many laws.
In 1815 Switzerland again became independent from France.
Other countries agreed at the Congress of Vienna that Switzerland was free and neutral.
The constitution of Switzerland that was made after a short civil war in 1848 was replaced in 1999.
Switzerland did not fight in World War I or World War II.
Since 2002, Switzerland is part of the United Nations.
It did not join the United Nations for 57 years because of its neutrality.
Switzerland is a republic.
Switzerland does not have the same kind of president as the United States or France.
Seven people (called ministers) do the job of president.
They are called the Federal Council in English, Bundesrat in German, Conseil Fédéral in French, Consiglio Federale in Italian and Cussegl Federal in Romansh.
Every year one of these people is made president.
The president is not more important than the other six people.
At present 3 of the 7 people are women.
Simonetta Sommaruga (President 2020)
Guy Parmelin (Vicepresident 2020)
There are two parts of parliament in Switzerland.
The Council of States and the National Council.
Only both together can make laws.
There are 46 people in the Council of States.
Every full canton of Switzerland can send 2 people.
There are 200 people in the National Council.
The biggest canton sends most people to the National Council.
The smallest 6 cantons can only send one person to the National Council.
The people of Switzerland can collect signatures if they do not like a new law or a law change.
This is called a referendum.
If enough people sign a referendum, the people vote.
The people can also collect signatures to change the constitution.
This is called an initiative.
The constitution is the basic law of a country.
Switzerland is not a member of the European Union, but it is member of the European Free Trade Agreement (EFTA).
The EFTA makes trade with other countries in Europe easier.
In 1999 Switzerland and the European Union made a contract.
This contract makes trade even easier.
They recently made two other contracts.
The banks of Switzerland and the insurance companies in Switzerland together produce eleven per cent of the gross domestic product.
Tourism is important in Switzerland.
There are many places for tourists.
Davos, St. Moritz, Pontresina and Flims are in Switzerland.
These towns are important both in winter (for skiing) and in summer.
Tourists also like the cities of Lucerne, Geneva, and Zürich.
In 2011 the pharmaceutical industry in Switzerland directly and indirectly employed about 135,000 people.
The companies Novartis and Roche are the second and third largest pharma companies in the world.
They both have invented many life saving drugs because of well developed research and development facilities.
The literature of Switzerland is divided according to the language used.
Most Swiss literature was written in German from 1291 until 1798.
French became popular in Bern and elsewhere in the 18th century and many words also in the German speaking parts of Switzerland come from the French and are not known to Germans.
Italian language and Romansch-Latin literature are less common in Switzerland.
Heidi, a book for children by Johanna Spyri, is the most famous book of Switzerland.
It is in the mountains in Graubünden.
Skiing, snowboarding and mountaineering are among the most popular sports in Switzerland.
Because of the large mountain range the nature of the country is well suited for such activities.
Bobsleigh was invented in St. Moritz.
The first world ski championships were held in Mürren (1931) and St. Moritz (1934).
St. Moritz hosted the second Winter Olympic Games in 1928 and in 1948.
Among the most successful skiers and world champions are Pirmin Zurbriggen and Didier Cuche.
Many Swiss are fans of football.
The national team or 'Nati' is widely supported.
Switzerland was the joint host, with Austria, of the Euro 2008 tournament.
Many Swiss also follow ice hockey.
In April 2009, Switzerland hosted the 2009 IIHF World Championship for the 10th time.
The National League A is the most attended league in Europe.
The many lakes in the country make Switzerland a good place for sailing.
The largest, Lake Geneva, is the home of the sailing team Alinghi.
They were the first European team to win the America's Cup in 2003.
They also won in 2007.
Tennis has become more popular.
Swiss players such as Martina Hingis and Roger Federer have won multiple Grand Slams.
Motorsport racecourses and events were banned in Switzerland after the 1955 Le Mans disaster.
There were exceptions for events such as Hillclimbing.
This ban was overturned in June 2007.
During this period, the country still had successful racing drivers such as Clay Regazzoni, Sebastian Buemi, Jo Siffert and successful World Touring Car Championship driver Alain Menu.
Switzerland also won the A1GP World Cup of Motorsport in 2007–08 with driver Neel Jani.
Swiss motorcycle racer Thomas Lüthi won the 2005 MotoGP World Championship in the 125cc category.
Traditional sports include Swiss wrestling or "Schwingen".
It is an old tradition from the rural central cantons and considered the national sport by some.
Hornussen is another native Swiss sport.
It is like a cross between baseball and golf.
Steinstossen is the Swiss version of stone put, a competition in throwing a heavy stone.
It is recorded to have taken place in Basel in the 13th century.
It is also central to the Unspunnenfest, first held in 1805.
English homepage of the Federal Authorities of the Swiss Confederation
The Swiss Confederation: A Brief Guide
Pictures from Switzerland
LOL, or lol, is an internet slang term that means "laugh(ing) out loud".
It is commonly mistaken for "lots of love."
LOL is often used in messages meaning "That is really funny."
It also means mute in Persian and is a native Dutch word (not an acronym) which means "fun" ("lollig" means "funny").
In Welsh, lol means nonsense - e.g., if a person wanted to say "utter nonsense" in Welsh, they would say "rwtsh lol".
LOL is usually used on the internet or when text messaging.
Words similar to "LOL"
lolz, lulz, lul, lawls, or lawl/lawlzies: Sometimes used instead of LOL, but can have other meanings.
LOOOOOL: For more emphasis.
Any amount of "OL"s can be added to the end of LOL.
LMAO: Stands for "Laugh my ass off".
Another way to say it is LMFAO ("Laugh my fucking ass off").
ROFL: For "rolling on the floor laughing".
It is often combined with LMAO to make ROFLMAO ("Rolling on the floor laughing my ass off").
Another way to write this is ROTFL.
ROTFLOL: Rolling on the floor laughing out loud; used by Weird Al in the song "White and Nerdy".
LEL: Basically lol; except used by those wanting to be different from the millions of internet users.
kek: The Japanese version of saying Lol.
LEL: Basically lol; except used by those wanting to be different from the millions of internet users
Toronto is the capital city of the province of Ontario in Canada.
It is also the largest city in both Ontario and Canada.
It is found on the north-west side of Lake Ontario.
The City of Toronto itself has a population of almost 3 million people.
Even more people live in the regions around it.
All together, the Greater Toronto Area is home to over 6 million people.
This makes it the biggest metropolitan area in Canada.
Toronto was created in 1793 by John Graves Simcoe as the capital of what was then called "Upper Canada".
At the time it was called the "Town of York" after the Duke of York.
The name was changed to Toronto in 1834.
With the Canadian Confederation in 1867, it became the capital of the newly created province of Ontario.
Toronto was one of two cities (along with Montreal in Quebec) that wanted to be the capital of Canada.
Queen Victoria decided that Ottawa should be the national capital because it was located between the two.
As the 19th century moved on, the city began to grow.
This was mainly because of immigration, where people from all over the world left their home and moved to Canada.
Many of the immigrants were Irish people.
They brought their Catholic faith with them when they left Ireland because of the Irish Potato Famine.
During World War I and World War II, Toronto was used to train members of the Canadian Army.
After the wars, even more immigrants came to the city.
The population was becoming so big that the Government of Ontario decided to create Metropolitan Toronto in 1954, combining a number of local municipalities.
These were Old Toronto, York, East York, North York, Etobicoke, and Scarborough.
By 1981, Toronto had more people than Montreal even though it was created after Montreal.
Because of that, the Ontario government decided to make Toronto a "megacity" in 1998.
The first mayor of Toronto was Mel Lastman.
As Toronto moved into the 21st century, it became host to a number of worldwide events.
These included World Youth Day in 2002, WorldPride in 2014, and the 2015 Pan American Games.
Toronto has a hot-summer humid continental climate (Köppen climate classification: Dfa).
Things to see and do
Toronto has a humid continental climate (Dfa in the Köppen climate classification).
This is because although the city is next to Lake Ontario, the lake is not big enough to keep its temperature mild.
As the biggest city in Canada and one of the biggest in all of North America, Toronto is a popular destination for tourists.
It is where you can find the CN Tower, which is the tallest free-standing (not supported) structure in the Americas and one of the Seven Wonders of the Modern World.
There are some other buildings, including the City Hall and the Rogers Centre, that are well known for their design style.
There are many skyscrapers, because many large banks of Canada and other companies have their main offices in Toronto, and the Toronto Stock Exchange which is the biggest stock market in Canada.
Because Toronto is the capital of Ontario, it is where the provincial government meets.
Visitors can see how the province is run by visiting the legislature in Queen's Park.
There are museums, including the Royal Ontario Museum, the Art Gallery of Ontario, the Ontario Science Centre, the Hockey Hall of Fame, and the headquarters of the Canadian Broadcasting Corporation.
In the suburbs of the city is the Toronto Zoo and Canada's Wonderland.
Many visitors also like to go to Niagara Falls, just an hour's drive away from Toronto.
Toronto is full of places to visit, eat, shop, and enjoy.
In the downtown area are shopping centres, including the Eaton Centre, St. Lawrence Market, and the Distillery District.
There are several theatres, many which are run by the Mirvish family.
The Four Seasons Centre for the Performing Arts, opened in June 2006, is home to the Canadian Opera Company and the National Ballet of Canada.
Across the harbor are the Toronto Islands, the best known of which is Centre Island.
Toronto has many sports teams.
Some of them belong to the most commonly-followed leagues in North America.
They include the Toronto Maple Leafs in ice hockey (NHL) and the Toronto Raptors in basketball (NBA), both of which play in the Air Canada Centre.
The nearby Rogers Centre is where the Toronto Blue Jays baseball team plays.
BMO Field in Exhibition Place is home to the Toronto Argonauts in Canadian football and Toronto F.C., a soccer club.
Toronto is a very multicultural city.
Different people from around the world have moved to Toronto to live since the 20th century.
There is a Chinatown, Little Italy, Little Tokyo, Greektown, Little Portugal, and other places where different cultures are kept alive.
These people hold festivals where they share their culture with others.
Among the most popular is the Canadian National Exhibition (CNE), which happens every year in August.
Like many cities around the world, Toronto has an airport, Toronto Pearson International Airport.
There are flights to many places in Canada and the rest of the world.
The airport is just northwest of the city centre.
Since 2015, there has been a train service, the Union Pearson Express.
It goes from the airport to Downtown in less than half an hour.
Toronto's main public transportation system is operated by the Toronto Transit Commission (TTC).
The main part of its public transport network is the Toronto subway system.
That system includes three heavy-rail rapid transit lines spanning the city, including the U-shaped Line 1 and east–west Line 2.
A light metro line also exists, exclusively serving the eastern district of Scarborough.
A discussion is underway to replace it with a heavy-rail line.
The TTC also operates an extensive network of buses and streetcars.
The streetcars serve the downtown core.
The buses provide service to many parts of the city not served by the sparse subway network.
The Government of Ontario also operates a commuter rail and bus transit system called GO Transit in the Greater Toronto Area.
GO Transit carries over 250,000 passengers every weekday (2013) and 57 million annually.
Most of them travel to or from Union Station.
GO Transit is implementing RER (Regional Express Rail) into its system.
Housing in Toronto was ranked as 10th-least affordable in the world.
The study compared Toronto with ninety other metropolitan areas in different countries.
Hong Kong came in as the least affordable place to live in.
Toronto Stations
CBLT CBC
CJCL 590
CHKT 1430
CFMT Omni
City of Toronto - Official city website.