the-french-artist/wikipedia_20220301.simple_sentence_split huggingface dataset:
Also, it is the only country in the world that is an enclave of a city, as all of the land around it is part of Rome, the capital of Italy.
The Vatican City is a city-state, because all its territory is urban and built-up.
The Vatican City is the headquarters of the Roman Catholic Church and its government, the Holy See.
Its head of state is the Pope which is, religiously speaking, the Bishop of Rome and head of the Roman Catholic Church.
The current Pope, Pope Francis, former cardinal Jorge Mario Bergoglio, was elected on 13 March 2013.
Established on 11 February 1929 with the Lateran Agreement (Patti Lateranensi) signed by Benito Mussolini and Pope Pius XI, the Vatican City is also important for its culture and art.
The Vatican's masterpieces are very well known in the world: St. Peter's Square, St. Peter's Basilica, the Sistine Chapel, the Vatican Museums and the Apostolic Palace, where the Pope lives.
There are also hundreds of other sculptures and pictures.
The Pope used to rule the Papal States, which included most of Italy.
Catholic popes had generally tried to stop Italy from becoming one country because they feared they would lose their control of at least one of the Papal States.
In 1861 Italy was unified under the King of Savoy, but Rome and Latium remained unconquered.
On September 20, 1870 Italian troops invaded.
Rome became capital of the new kingdom.
The Pope claimed he was a prisoner of the Italian state and excommunicated all the people who helped invade the Papal state.
This stopped Catholics from taking part in public life under Catholic government.
In 1929 Benito Mussolini, decided to sign an agreement with the Holy See, called the Lateran Treaty, which created the Vatican State.
Another treaty gave the Vatican money each year to compensate for the lost territories.
Politics and Government
The government structure is theocracy with the pontifical leader being the highest authority.
The pope is elected by the College of Cardinals which can lead the Roman Catholic Church and the city-state itself.
The Pope also holds the title of "Bishop of Rome".
Vatican City has a population of 453 people, and 246 of them are citizens.
The citizens of the Vatican include the Pope, all the cardinals, all the ambassadors (who are called nuncios) and other diplomats, all the Swiss Guards, and other important people.
Also, there are 372 Vatican citizens who live in other countries, including cardinals and nuncios.
Vatican citizenship cannot be passed to children and spouses; and, except for the Pope and cardinals, Vatican citizenship is lost when the term of office comes to an end, for the Swiss Guards, nuncios and diplomats, and other people working for the Vatican.
The Vatican does not have a law declaring an official language.
Italian is the main language used.
The Holy See's official language is Latin.
The official religion of the Vatican is Roman Catholic Christianity, and because the state is ruled by a Pope, it is a theocracy.
1929 establishments in Italy
Velocity is a measure of how fast something moves in a particular direction.
To define it needs both magnitude and direction.
If an object moves east at 9 metres per second (9 m/s), then its velocity is 9 m/s to the east.
The idea behind this is that speed doesn't tell us in which direction the object moves in a given frame of reference.
Speed is one part of velocity, direction is the other part.
Depending on the frame of reference, the velocity can be defined with many mathematical concepts required for making the correct analysis.
Velocity in one-dimensional motion
Average velocity
Instantaneous velocity
Velocity in two-dimensional motion
The concept of velocity allows us to consider two different means of calculating the velocity.
Two-dimensional motion requires us to use vector notation to define the physical quantities found throughout the kinematics.
Distinction between average velocity and instantaneous velocity regarding two dimensional motion
where: is the total distance traveled in a given time interval .
Each of these quantities can be calculated by substracting two different values intertwined within the given quantity, hence give the desired .
When , we can see that .
Taking that into consideration we can conceptualize this rate of change between displacement vector and interval of time using mathematical analysis (most notably- Calculus)
Relative velocity
Velocity can also be measured by comparing the motion of two objects.
This is called relative velocity.
The second object is called the reference frame.
To find the relative velocity, subtract the velocity of the reference frame from the velocity of the first object.
For example, Earth moves at 67,000 miles per hour around the Sun.
Usually, we do not care about this motion.
So we subtract the vector that represents Earth's motion from the total motion.
A virtual community is a group of people who share an interest, hobby or set of views.
The people in it may come from many different places.
They talk with each other using technology, such as the Internet, telephone calls, texting, video calls and email.
How virtual communities communicate
Instant messengers
Internet Forums (message boards)
Websites like social network services
Conference calls (where more than 2 people can talk at one time)
A newsletter
A magazine
"The Web" redirects here.
For other uses, see Web (disambiguation).
The World Wide Web ("WWW" or "The Web") is the part of the Internet that contains websites and webpages.
It was invented in 1989 by Tim Berners-Lee at CERN, Geneva, Switzerland.
Sir Tim Berners-Lee created a new markup language called HTML.
Websites are composed of pages linked by hypertext links that are written in HTML.
The software to see the World Wide Web is called a web browser.
One also needs a connection to the Internet.
Many companies nowadays offer limited website hosting allowing one to make websites that can be displayed on the World Wide Web like any other domain (www.stuff.com) site.
These sites usually make money from advertisments instead of fees.
Invention of WWW
While working at CERN in 1989, Sir Timothy John Berners-Lee developed the World Wide Web.
He was a computer scientist from England.
Tim Berners-Lee was a Professorial Fellow of Computer Science at Oxford University and a professor at Massachusetts Institute of Technology.
A wiki is a type of a website that lets anyone who can access the wiki create and change its pages.
The word is Internet slang.
The word wiki is short for WikiWikiWeb.
Wikiwiki is a word from the Hawaiian language, meaning "fast" or "speed".
Examples of wikis include Wikipedia, Everipedia, Citizendium, Scholarpedia Conservapedia, Wiktionary and Wikibooks.
Every wiki can be changed, or edited, by anyone who has an account on the wiki, or by everyone in the world if the wiki allows it.
Some important pages can only be changed by certain users.
Wikis are central places where we all can share information, people can add new information, and then people read them.
Wikis allow information from all around the world to be collected.
On a wiki, people can write pages by collaboration.
Pages are watched closely to see whether changes are good or bad.
If one person writes something wrong, another can correct it.
Other users can also add something new to the page.
Because of this, the page gets better when people change it.
Administrators can block someone from editing if they vandalize, or for other reasons.
Users can also discuss things on wikis.
Discussion can help people understand things better and get a chance to tell their views.
In Wikipedia the talk pages are for that, but in some wikis, the article and the discussion are in the same page.
Wikis can be used for different things; not all wikis follow the same rules for using them.
For example, the purpose of Wikipedia is to write articles for an encyclopedia.
That is why in Wikipedia, people do not want general discussion that does not help in writing articles.
Ward Cunningham started the first wiki in March 1995.
Many people liked it, and wrote there, after which they started similar websites such as Wikipedia.
MediaWiki is the most used software for wikis and is the software used for Wikipedia and many other Wikis.
JSPWiki is one of many others. "
Wiki" is also sometimes an abbreviation for Wikipedia.
Most wikis can be edited by anyone and everyone.
Some wikis are even available to people without an account, so sometimes wikis will become a target for vandals to add unwelcome, disruptive or even misleading content.
There are many ways to prevent this.
Individual pages can be protected to allow only certain users, or only those with an account, to edit them.
Administrators can also block users who make repeated vandalous edits after a minimum of a single warning.
Vandalism may not be stopped totally, but regular, careful checking can limit the amount of disruptive edits you will see in a day.
Wikis
A website is a set of webpages that are joined together.
People look at websites with a computer of some kind, sometimes including the computer inside mobile phones and televisions.
The websites are kept on computers called web servers.
There is almost always a single homepage which has links to other pages that are part of that "site".
Sometimes it has links to pages that are part of other "sites" as well. (
Note that net jargon uses the word site, which also means a physical place in the real world, to mean a web URL).
A home page serves as the introduction page of a website.
Websites can be used to advertise or sell things.
They can also be used to talk to other people.
A blog is a website where the location of the material is less relevant than who writes it, and which is more focused on dialogue.
Very often the people who use blogs dislike the word "site" since it implies a controlled place.
Sites are good for looking up information on the computer.
There are many different types of website based on their purpose and the type of organisation they are created for.
Weblog (also known as blog).
Wiki (A website where anyone can edit the pages).
Content Management System (Software that can edit web pages through a WYSIWYG editor).
Search engine (A website like Google, Bing and DuckDuckGo which you can use to search the web).
Social networking sites (Like Facebook, Twitter and Instagram which allows you to interact with people on the internet).
Quiz websites like Quotev, Buzzfeed, Allthetests and GoToQuiz are websites used to look at Quizzes, fan-fictions and Surveys about Television, Radio and Music and other things done in Society.
Video Websites like YouTube exist to look at Videos of people and things.
Online forum, discussion, Q&A, and community website.
Membership website
Application Websites, Nowadays simply known as Apps are Websites that are Square shaped and require more difficulty to access and usually ask you to download their App to access specific things.
.org websites are websites that are organisations.
.uk, .au and .us are types of websites that are only available in the United kingdom, Australia and the United States, but some can be used outside of these countries.
.io websites are usually online game websites that run on an internet thing called an IO, which has some kind of meaning, but they can be accessed like any other website through the internet.
There are other types of websites that aren't available to the public that end in a .
followed by random letters but there are too many to list.
Users can access any website by using a URL.
This is the website address which is shown near the top of the web browser.
The homepage and the rest of the site usually have the same words at the start of the URL — for instance, pages at the Simple English Wikipedia always start "http://simple.wikipedia.org/..." but are different after that.
However, if a person does not buy a domain name, the website could be an IP Address.
An example of an IP address is 172.217.13.228.
Website builder software is usually a collection of software tools that allow the construction of websites without manual code editing.
Several hosted website services have website builder software built-in.
A word is something spoken by the mouth, that can be pronounced.
In alphabetic writing, it is a collection of letters used together to communicate a meaning.
These can also usually be pronounced.
A logogram is also a word.
Some words have more than one meaning, for example 'spring' can refer to the season, the device, or a conjugation of the verb.
These are homonyms.
Some words have different pronunciation, for example, 'wind' (the noun) and 'wind' (the verb) are pronounced differently.
Some words have different spelling for example 'color' and 'colour', which are both correct.
Color is used in American English and colour is used in British English.
Some words can be only one letter, for example "a" and "I" in English.
Besides English, other languages have their own words.
When written with an alphabet, words are usually separated by a space.
When written with ideograms, each word is usually a separate symbol.
Words can be invented.
This is called neologism.
For example, radar was originally an acronym but became an actual word.
Two words may be joined to make a compound word.
Fuller definition
A word is the smallest thing which can be said with meaning.
For example, hello is a word.
This contrasts with a morpheme, which is the smallest unit of meaning but may not stand on its own.
A word may consist of a single morpheme (for example: oh!,
rock, red, quick, run, expect), or several (rocks, redness, quickly, running, unexpected), whereas a morpheme may not be able to stand on its own as a word (in the words just given, these are -s, -ness, -ly, -ing, un-, -ed).
A web browser is a computer program application for reading pages of the World Wide Web.
Since the late 1990s, most personal computers and mobile phones and other mobile devices have a browser.
Web browsers are used by people to find and look at websites on the Internet.
The first web browser was created in 1990.
Many web browsers are available for free.
All web browsers can go to websites but each browser has good things and bad things about it.
For example, some browsers focus on data security and keeping computers safe from viruses.
Other browsers are made so that web pages appear on-screen faster.
Internet Explorer included with Microsoft Windows
Microsoft Edge, a more modernized version of Internet Explorer, included with Windows 10
Web browsers and HTML
A webpage is one page of a website.
Every web page has a web address.
A web browser goes to a web page using a web address.
It downloads the HTML file stored at that address.
Its browser engine then reads and translates the HTML file.
The browser will then show the webpage on the screen as text, images and clickable links.
What is browser?
Video by Google
Web Browser -Citizendium
Spider webs are woven traps usually used by spiders to catch insects
Web is a common short name for the World Wide Web
Web is a word for the tissue (biological) between fingers and toes, such as the webbed feet of ducks and other waterfowl, or material with a similar purpose, such as between the thumb and finger of a baseball glove
A webpage (or web page) is a document from the internet which can be seen with a web browser.
Web pages each have a URL or address, which is how a page is found, and is different for every page.
When a webpage is part of a larger group of pages managed by a company, person, or organization, it is part of a website.
Pages can have words, pictures, videos, and links.
Links are ways to get to other web pages.
For example, this article is a webpage.
It has the URL https://simple.wikipedia.org/wiki/Webpage, and is part of the Wikipedia website.
It has words and links.
The links in this page are shown in blue and can be clicked to go to other webpages.
Web pages are usually stored in HTML code which describes what to show on the page like words or pictures.
Web pages also use two other types of code to tell the page how to work:
Cascading Style Sheets (or CSS) is a code used to tell the page how to look.
JavaScript (or JS) is used to change the words, style, or pictures on the page.
Wiktionary is a wiki-based project to develop a multilingual online dictionary, or a group of meanings for words, in the form of a wiki.
There are many languages of Wiktionary.
Wiktionary is also a thesaurus.
Wiktionary is run by the Wikimedia Foundation, which also runs Wikipedia.
The English Wiktionary currently has over 6.1 million pages  and 3.5 million users.
Much like Wikipedia, the Wiktionary is run in several different languages that can be selected from its main page.
In 2006, there was a vote for the change of the logo of Wiktionary.
The original logo of only words was replaced.
However, there were very few people who voted in this contest.
Therefore, smaller wikis used the newer logo but the English Wiktionary stayed with the same logo.
In 2009, there was a second contest for a newer logo (pictured).
This was a step to make all the Wiktionaries to have the same logo on all projects.
However, the English Wiktionary still did not use the new logo.
The Simple English Wiktionary voted on the new logo on November 30, 2010 and the community decided the new logo to use it as their logo.
However, no changes were made to the logo and the discussion was thus forgotten.
Simple English Wiktionary main page
English Wiktionary main page
Simple English Wiktionary mobile version
English Wiktionary mobile
Microsoft Windows is an operating system for computers made by the United States-based company Microsoft.
Windows is used by almost 90% of desktop and laptop computers.
The first version of Windows, Windows 1.0, came out on November 20, 1985.
The newest version, Windows 11, came out October 5, 2021.
Most personal computers made after 2015 come with Windows 10.
However, some older or cheaper personal computers may come with Windows 8.1 or Windows 7.
Windows makes it easier to run programs (applications) than MS-DOS did.
DOS required typed commands to make the computer do something.
DOS required correct syntax of each command.
Making mistakes caused the computer to usually give an error message and do nothing.
Users control their Windows computer by its graphical user interface (or GUI for short).
It only needs a keyboard or a mouse to work.
In later versions, a touch screen works as well.
However, using both a keyboard and a mouse makes many tasks easier.
By clicking a few buttons on the screen, Windows helps keep your files safe, and easier to change and move.
Versions of Windows after 2005 make it even easier for some users with disabilities because these versions have touch screens.
For use of a touch screen, some mobile devices come with Windows.
Tablet computers and smartphones such as Microsoft Surface and Microsoft Lumia use Windows.
WordPad – to write simple documents, typically using words/text.
Windows Photo Viewer – to look at pictures.
Microsoft Paint – to make simple drawings or change pictures.
Microsoft Edge web browser – to use the Internet to look at web pages and download files.
Windows DVD Player to watch videos.
Windows Groove to play and listen to music
Windows has several kinds of applications/programs available.
Popular applications include games, word processors (to write words) or additional programs like Adobe Flash Player (to watch some videos and play many games on internet sites).
Adding new applications to Windows is called "installing".
Applications can be bought/purchased on a CD or DVD.
Applications can also be downloaded from the Internet.
Some internet applications can be downloaded for free, and others can be bought using the internet.
Many users complain that Windows creates problems for them.
Some users complain that Windows made their computers slower when they changed from DOS.
Many people also complain about problems that make their computer less safe to use, even though Microsoft tries to fix these problems.
Many computer viruses are created to infect computers running Windows since it is such a popular operating system.
Windows was the most popular operating system until recently (today mobile operating systems such as Android are more popular).
The Microsoft Windows website
The Windows Team Blog – Official blog of the Windows Team at Microsoft
Microsoft operating systems
A window is an opening in a wall or roof of a building, in a car etc.,
to let air and light in.
It is usually filled with a sheet of glass.
There can be many different shapes and sizes, including rectangular, square, circular, or irregular shapes.
Some windows include coloured glass.
Windows are usually transparent so that people can see through them.
Before glass was used in windows, people in Asia used paper to fill the hole in the wall.
The paper would let light in.
Types of window
These are different types of windows.
Cross-window
A fixed window is a window that cannot be opened.
It is made to allow light to enter.
The windows in churches are usually fixed.
Single-hung sash
Double-hung sash
A casement window is a window with a sash that has a hinge that swings in or out like a door.
Casement windows are usually held open using a casement stay.
A skylight is a window built into a roof.
This type of window allows natural daylight and moonlight to enter.
Roof lantern
A roof lantern is a glass structure that has lots of different colors.
It looks like a small building.
It is built on a roof for day or moon light.
A stained glass window is a window that is made up of pieces of colored glass.
The colored glass can be transparent, translucent or opaque.
It usually shows people or places.
Usually the glass in these windows is separated by lead rods.
Stained glass windows are very common in churches.
How they are made
Different materials are used when making a window.
For the frame of the window wood, polyvinyl chloride, composite, aluminium, steel, fiberglass are used.
Many windows have movable window coverings such as blinds or curtains.
They keep out light, give extra insulation.
It also ensure privacy.
Windows allow natural light to enter.
But too much can have bad effects such as glare and heat gain.
Windows (architecture)
Wine is an alcoholic drink.
The word wine is usually used to talk about drinks made from the juice of grapes, although people sometimes call alcoholic drinks made from the juice of other fruits (such as plums or blackberries) "wine".
This article only deals with wine made from grapes.
Different types of wine
There are two main types of wine, red wine and white wine.
Red wine is made using the skins of the grapes.
The skins give the wine a dark color, and chemicals called tannins that taste bitter.
Red wine can be sweet or "dry", meaning low in sugar.
White wine is made without the grape skins at all, so it is usually less bitter and more acidic.
Like red wines, they can be sweet or dry.
Rosé wine (a French word meaning "pink") is in between: it has some flavor and color from the skins, but not as much as a red wine.
Wine sometimes has bubbles in it, called sparkling wine.
Sparkling wine can be red, white, or rosé, but is usually white.
It can be made in any country, but the best-known sparkling wines are champagne, which comes from France, and prosecco, from Italy.
Wine making
Wine making begins with growing red or white grapes.
Wine grapes have thicker skins and bigger seeds compared to table grapes for eating.
After the grapes are ripe, they are picked off the plants.
There are different ways of picking (for example, using machines, or picking by hand, in the day, or at night).
After harvest, the grapes are crushed to release their juice, which is very sugary.
Before, this was done by people stomping on grapes with their bare feet.
Today, machines are used, but people sometimes use their bare feet in festivals.
The person making the wine also decides now if the wine will be red, white, or rose:
If the grape skins sit in the juice a long time, the wine will be red.
If the grape skins sit in the juice a short time, the wine will be rosé.
If the grape skins do not sit in the juice at all, the wine will be white.
Next, the sweet grape juice is fermented, by adding yeast.
In a few days, the yeast turns the sugar into alcohol, and also releases carbon dioxide.
After fermenting, the wine is stored for a while (called "aging").
The person making the wine can make different choices, which will change the flavor of the wine.
They can choose to store the wine in a steel container, or a barrel made of oak wood.
If they choose wood, the wine will absorb some of the wood flavor, which wine drinkers call "oakiness".
This process can take only a couple of weeks, up to several years, depending on what kind of flavor the wine maker wants.
Lastly, the wine is bottled and sent to a customer, restaurant or store to be enjoyed.
Wine and people
Wine is a popular drink in many countries.
The countries that drink the most wine (using numbers from the year 2000) are:
Wine is made in many countries.
The countries that make the most wine (using 2015 numbers) are:
Water () is a transparent, tasteless, odorless, and almost colorless chemical substance and covers over 70% of Earth's surface.
No known life can live without it.
Lakes, oceans, seas, and rivers are made of water.
Precipitation is water that falls from clouds in the sky.
It may be rain (liquid) if it is warm, or it may be frozen if it is cold.
If water gets very cold (below ), it freezes and becomes ice, the frozen variant of water.
If water gets very hot (above ), it boils and becomes steam or water vapor.
It is moved around in the water cycle.
Physical chemistry of water
Water is the only chemical substance on Earth that exists naturally in three states.
There are over 40 anomalies (strange things) about water.
Unlike most other liquids such as alcohol or oil, when water freezes, it expands by about 9%.
This expansion can cause pipes to break if the water inside them freezes.
Water is a molecule made of two hydrogen atoms and one oxygen atom.
Its chemical formula is H2O.
Things having something to do with water may have "hydro" or "aqua" in their name, such as hydropower or aquarium, from the Greek and Latin names for water.
It is also called the "universal solvent", because it dissolves many other compounds.
Uses of water
Plants and animals (including people) are mostly water inside, and must drink water to live.
It gives a medium for chemical reactions to take place, and is the main part of blood.
It keeps the body temperature the same by sweating from the skin.
Water helps blood carry nutrients from the stomach to all parts of the body to keep the body alive.
Water also helps the blood carry oxygen from the lungs to the body.
Saliva, which helps animals and people digest food, is mostly water.
Water helps make urine.
Urine helps remove bad chemicals from the body.
The human body is between 60% and 70% water, but this value differs with age; i.e. a foetus is 95% water inside.
Water is the main component of drinks like milk, juice, and wine.
Each type of drink also has other things that add flavor or nutrients, things like sugar, fruit, and sometimes alcohol.
Water that a person can drink is called "potable water" (or "drinking water").
The water in oceans is salt water, but lakes and rivers usually have unsalted water.
Only about 3% of all the water on earth is fresh water.
The rest is salt water.
Many places, including cities and deserts, don't have as much water as people want.
They build aqueducts to bring water there.
Though people can survive a few months without food, they can only survive for a day or two without water.
A few desert animals can get enough water from their food, but the others must drink.
Water has no smell, taste, or color.
Water is also used for recreational purposes, see list of water sports.
Water is used as both the coolant and the neutron moderator in most nuclear reactors.
This may be ordinary water (called light water in the nuclear industry) or heavy water.
Water is also used for washing a lot of objects.
Goods, services and people are transported to other countries in watercrafts on bodies of water.
Water is used in chemical reactions as a solvent or reactant.
Water is also used in fire fighting.
Water is also used for cooking.
Dihydrogen monoxide parody
The dihydrogen monoxide parody involves calling water by the unfamiliar chemical name "dihydrogen monoxide" (DHMO) and listing some of its harmful effects in an alarming way.
Some examples include talking about how "it causes burning, suffocation and corrosion," when it is actually just talking about hot water, drowning and rust.
Sometimes the parody calls for it to be banned and/or labelled as dangerous.
The prank works because it takes advantage of people's misunderstanding.
Calling water by an unfamiliar name and making it sound like a harmful chemical can make people think it is dangerous.
"Dihydrogen monoxide" is an alternative chemical name for water, but nobody uses it.
The word "dihydrogen" means two hydrogens, and "monoxide" means one oxygen.
The chemical formula of water has two hydrogens and one oxygen.
The parody gained most of its popularity in the 1990s, when a 14-year-old named Nathan Zohner collected anti-DHMO petitions for a science project about gullibility.
Zohner fooled a lot of people, which has led to his project being used in lessons about critical thinking and the scientific method.
Origin of the Earth's water
The weirdness of water
A BBC short item  explains that every molecule on Earth has existed for billions of years, and all of them came from elsewhere.
Water is alien because it arrived on asteroids and comets.
It is the second most common molecule in the universe.
Why is it not a gas?
It is made of two very light elements.
Ice floating on water is also an oddity.
Also, hot water freezes faster than cold, and no-one knows why this is.
Molecules of water can move up against the force of gravity (that is due to surface adhesion).
Water in the universe
On 22 July 2011, a report described the discovery of a gigantic cloud of water vapor containing "140 trillion times more water than all of Earth's oceans combined" around a quasar located 12 billion light years from Earth.
According to the researchers, the "discovery shows that water has been prevalent in the universe for nearly its entire existence".
Water has been detected in interstellar clouds in our galaxy, the Milky Way.
Water probably exists in abundance in other galaxies, too.
Its components, hydrogen and oxygen, are among the most abundant elements in the universe.
Most other planetary systems are likely to have similar ingredients.
Origin of water on Earth: Possibilities
We do not know exactly how the Earth came to have so much water.
It is everywhere in the Universe, but it is uncommon for a place to have so much.
Reasoning from first principles, every element except hydrogen has been formed in stars.
Therefore oxygen was originally formed in stars.
The formation of water is not a problem: it is exothermic, so forming the molecule from its atoms does not need outside energy.
But to explain why the Earth has so much compared to, for example, Mars, is not easy.
It is an undecided problem in planetary geology.
For a while, people thought Earth’s water did not come from the planet’s region of the protoplanetary disk.
Instead, it was thought that water and other volatiles must have been delivered to Earth from the outer Solar System later in its history.
But hydrogen inside the Earth did play some role in the formation of the ocean.
The two ideas may each be partly right.
Water was delivered to Earth by impacts from icy planetesimals  (asteroids) in the outer edges of the asteroid belt.
How much is not known.
Water vapor is the gas form of water and is found in:
Atmosphere of the Sun: It has small amounts of water.
Atmosphere of Mercury: It is composed of 3.4% of water.
Mercury has large amounts of water in its exosphere.
Atmosphere of Venus: It is composed of 0.002% of water.
Atmosphere of Earth: It is composed of 0.4% of water all over the atmosphere.
There is usually around 1–4% of water at the surface of the Earth.
Water vapor is also found in the extremely thin atmosphere of the Moon in small amounts.
Atmosphere of Mars: It is composed of 0.03% of water.
Atmosphere of Ceres.
Atmosphere of Jupiter: It is composed of 0.0004% ice.
There is also water in its moon Europa.
Atmosphere of Saturn: It is has water in the form of ice.
Enceladus is composed of 91% of ice and ice is also in Dione's exosphere.
Atmosphere of Uranus: Ice is found in small amounts.
Atmosphere of Neptune: Ice is also found deep in the atmosphere of Neptune.
The atmosphere of extrasolar planets such as HD 189733 b and HD 209458 b, Tau Boötis b, HAT-P-11b, XO-1b, WASP-12b, WASP-17b, and WASP-19b.
Stellar atmospheres: Water vapor is found in giant hot stars such as Betelgeuse, Mu Cephei, Antares and Arcturus.
Liquid Water
Liquid water is found on Earth.
It covers about 71% of the surface of the Earth.
Liquid water is sometimes found in small amounts on Mars.
Scientists believe that liquid water is in the moons Enceladus, Titan, Europa and Ganymede.
Frozen Water
The frozen form of water (ice) is found in:
Mars: Water ice is found at the north and south poles of Mars.
Earth and the Moon: It is mainly found as ice sheets on Earth and in craters and volcanic rocks in the Moon.
Jupiter's moons: It is found on Europa, Ganymede and Callisto.
Saturn: It is found in the planetary rings of Saturn.
It is also found in Titan and Enceladus.
Pluto and Charon
Comets and other objects in the Kuiper belt and Oort cloud.
Water Citizendium
Importance of Water
Hydrogen compounds
Oxygen compounds
A want is a wish or a desire for something.
If a person would like to have something, but can choose not to have it, that thing is wanted or can be called a want.
To want is not the same as to need, which is when someone must have something.
People often talk about needing a thing, when they really just want it.
Wants can be for the same things as needs.
For example, a person can need to eat food and can want to eat cake.
If there is no cake then he or she may have to eat something else, perhaps bread.
The need is no longer so important (the person is no longer hungry) although the want may still be there.
If there is cake, then the person's needs and wants can both be met.
In economics, a want is about goods or services.
Choice is how to satisfy a want, when there are different ways to do this.
Want can also be the idea of what it means to be poor, hungry or with no money.
Charles Dickens wrote a famous book called A Christmas Carol in which there are two children, named Want and Ignorance.
War is a situation or a period of fighting between countries or groups of people.
A war generally involves the use of weapons, a military organization and soldiers.
War is a situation in which a nation enforces its rights by using force.
Not every armed conflict is a war.
A fight between individuals, between gangs, drug cartels, etc.
is not considered a war.
However, most wars are called armed conflicts.
International humanitarian law is a set of rules that tries to limit the effects of wars.
International Humanitarian Law recognizes two kinds of wars.
"International armed conflicts" between two or more states.
"Non-international armed conflicts" as being between a government and a group that is not a government or one that is between two such groups.
Karl von Clausewitz wrote in his classic book, On War, that "war is a mere continuation of policy with other means.”
Clausewitz viewed war as a political instrument.
His book about military philosophy remains the most influential work on the history and strategy of war.
An earlier authority on war was Sun Tzu.
In his book The Art of War, Sun Tzu saw war as a necessary evil.
It was something people do.
Wars have been fought to control natural resources, for religious or cultural reasons and over political balances of power.
They have been fought over legitimacy (correctness) of particular laws.
They have been fought to settle arguments about land or money, and many other issues.
The reasons behind any war are often very complex.
While a war can start for just about any reason, there is usually more than one cause.
War and the beginning of nations
From the earliest times, individual states or political factions have used war to gain sovereignty over regions.
In one of the earliest civilizations in history, Mesopotamia, they were in a near constant state of war.
Ancient Egypt during its Early Dynastic Period came about by war when Lower and Upper Egypt were joined together as one country, about 3100 BC.
The Zhou Dynasty ruled Ancient China came to power in 1046 through war.
Scipio Africanus (236-183 BCE) defeated Carthage leading Ancient Rome to begin a conquest of the known world.
Philip II of Macedon (382-336 BCE) united a group of city-states to become Ancient Greece.
Kinds of war
Sometimes, people don't see a difference between fighting between countries or people, and the formal declaration of a state of war.
Those who do see this difference usually only use the word "war" for the fighting where the countries' governments have officially declared war on each other.
Smaller armed conflicts are often called riots, rebellions, coups, etc.
One country may send forces to another country for a variety of reasons.
Sometimes it is to help keep order or prevent killings of innocents or other crimes against humanity.
It may be to protect a friendly government against an uprising.
Here it may be called a police action or humanitarian intervention instead of a war.
Some people think it's still a war.
Another kind of war existed from 1947 until 1991 called the Cold War.
This started when diplomatic relations between the United States and the Soviet Union broke down.
Both countries had nuclear weapons and both stood ready to use them against the other.
But there was no actual war between the two.
It ended with the fall of the Soviet Union in 1991.
The cold war was also called a containment where the United States tried to prevent the spread of communism to other countries.
During the cold war, the major powers did not fight themselves, but often backed third parties in what was called a proxy war.
The Vietnam War is often given as an example of a proxy war.
But proxy wars happened long before the cold war and are still happening.
A war between peoples and groups in the same country is known as a civil war.
It is generally agreed there are two things that make a war a civil war.
It must be a struggle between groups in the same country or state over political control or to force a major change in the government's policy.
The second criterion is that more than 1000 people have to have been killed, with a minimum of 100 from each side.
The American Civil War is an example of a civil war.
While the figures are mere estimates, the total casualties are thought to be about 750,000.
Only in the last 150 years or so, have states agreed on international laws to limit warfare.
This has been mainly for humanitarian reasons.
The Geneva conventions and the Hague Conventions are two examples of agreements that establish laws governing wars.
Collectively, these are usually called International humanitarian law (IHL).
Because these are established laws, they restrict those engaged in armed conflicts to follow the IHL.
Also, a country must not only respect the law but they also need to make sure other countries respect it as well.
They cannot turn a blind eye (meaning pretend they do not see a thing) to countries who are not following IHC.
The first of these was the Geneva Convention in 1864.
It became international law with the signatures of 100 countries.
Peace, the word which is its opposite meaning - where there is peace, this means that there is no war.
List of wars
List of battles
Correlates of War Project
War and Civilization - Episode 1: First Blood (History Documentary); YouTube
History Channel Documentary - Sun Tzu The Art of War:YouTube
Yiddish is a language used by some Jews.
At first, it was a dialect of German  that Jews began to use in Europe about 1000 years ago.
It was and still is used in the United States, especially in New York City, and other countries that now have Jews.
Most Yiddish words come from German, but many words are also from Hebrew and Slavic languages, especially Polish, and some from French, Hungarian and Latin.
Yiddish is written usually by the Hebrew alphabet.
European Charter
Di Velt fun Yidish: Audio Stories
One year is about 365 days long (except in a leap year).
It is the time it takes the Earth to go completely around (orbit) the sun once.
A year is actually 365.25 days long, but a calendar has 365 days, except in a leap year.
a solar year is based on the seasons.
The Gregorian calendar is based on the solar year.
The solar year is 365 days long.
A tropical year (also known as a solar year) is the time that the Sun takes to return to the same position in the cycle of seasons, as seen from Earth; for example, the time from vernal equinox to vernal equinox, or from summer solstice to summer solstice.
The word "tropical" in this sense comes from the Greek tropikos meaning "turn".
a lunar year is based on the moon and is usually 12 lunar months (29 days, 12 hours, 44 minutes each) or 354 days long.
a sidereal year measures the time between when a selected fixed star is highest in the night sky.
an anomalistic year is the difference between the times when the Earth gets closest to the sun.
an eclipse year is the time between node passages.
This is when the sun moves through a part of the sky where it is possible for the sun, Earth and moon to be in a line.
It is also when eclipses can happen.
Solar and lunar years are used by different calendars for daily life.
The other measurements are used by astronomers.
Ma (for meganum) — a unit of time equal to one million years.
The suffix "Ma" is often used in scientific disciplines such as geology, paleontology, and astronomy to signify very long time periods into the past or future.
The simpler term "mya" for "million years ago" is generally preferred on this wiki as being intuitively more simple for non-technical readers.
Units of time
You is a second-person English pronoun.
The word can be singular or plural.
It is what a person says when he or she is addressing another person in second person.
Sometimes, just using the English letter "u" is acceptable, and "ur" for the words "you're" and "your".
This is very informal, and is mostly used in texting.
Yard (land), an open space around a building.
For instance, the space around a school is called a school yard.
A yard is used by humans and their pets.
If there is wild space next to it, like forest land, swamp land, a beach or a lake, this will not normally be considered "part of" the yard – the yard ends at the edge of it.
Yard (sailing), a spar on a traditional sailing ship
Brickyard, a place where bricks are made or stored
The Chinese language is the group of languages used by Chinese people in China and elsewhere.
It forms part of a language family called the Sino-Tibetan family of languages.
Chinese includes many regional language varieties, the main ones being Mandarin, Wu, Yue and Min.
These are not mutually intelligible and many of the regional varieties are themselves a number of non-mutually-intelligible subvarieties.
As a result, many linguists refer to these varieties as separate languages.
'Chinese' can refer to the written or the spoken languages.
Although there are many spoken Chinese languages, they use the same writing system.
Differences in speaking are reflected in differences in writing.
Official China adopts a similar policy to the one in the Soviet Union, using one official language so people can understand each other.
The Standard Chinese language is referred to as Mandarin in English, "Pǔtōnghuà" or "common to everybody speech" in mainland China and "Guóyǔ" or "language of the whole country" in Taiwan.
All official documents in Pinyin are written in Mandarin and Mandarin is taught all over China.
It is also a standard for language teaching in some other countries.
Chinese is used by the Han people in China and other ethnic groups in China who are declared Chinese by the Chinese government.
Many people in autonomous regions of China speak other languages.
Chinese is almost always written in Chinese characters.
They are symbols that have meaning, called logograms.
They also give some indication of pronunciation, but the same character can get very different pronunciations among the different kinds of Chinese.
Since Chinese characters have been around for at least 3500 years, people in places far from each other say them differently, just as "1, 2, 3" can be read differently in different languages.
Chinese people needed to write down pronunciations in dictionaries.
Chinese does not have an alphabet, so how to write down sounds was a big problem in the beginning.
Nowadays the Mandarin language uses Hanyu Pinyin to represent the sounds in Roman letters.
All the Chinese languages (or dialects) use tones.
This means that they use high and low pitches to help make differences in meaning clear.
Different languages or dialects of Chinese
The Chinese language is like a big tree.
The base of the tree started thousands of years ago.
It now has several main limbs.
Some people call "just a branch" what other people call a main limb, so you can say there are six or seven main limbs.
Each of these main limbs splits off into branches about the way there are branches of English spoken in Great Britain, the United States, Australia, India, and so forth.
Just as the Romance languages all come from the area around Rome and are based on Latin, the Chinese languages all have some common source, so they keep many common things among them.
Guan ("Northern" or Mandarin), 北方話/北方话 or 官話/官话 (about 850 million speakers),
Wu, 吳/吴, which includes Shanghainese (about 90 million speakers),
Yue (Cantonese), 粵/粤 (about 80 million speakers),
Min (Hokkien, which includes Taiwanese), 閩/闽 (about 50 million speakers),
Xiang, 湘 (about 35 million speakers),
Hakka, 客家 or 客 or "guest family" speech (about 35 million speakers),
Gan, 贛/赣 (about 20 million speakers)
Traditional and simplified characters
In 1956, the government of the People's Republic of China made public a set of simplified Chinese characters to make learning, reading and writing the Chinese language easier.
In Mainland China and Singapore, people use these simpler characters.
In Hong Kong, Taiwan and other places where they speak Chinese, people still use the more traditional characters.
The Korean language also uses Chinese characters to represent certain words.
The Japanese language uses them even more often.
These characters are known in Korean as Hanja and in Japanese as Kanji.
A Chinese person with a good education today knows 6,000-7,000 characters.
About 3,000 Chinese characters are needed to read a Mainland newspaper.
However, people who have learned only the 400 most frequently used characters can read a newspaper—but they will have to guess some less-used words.
Here are some samples of some words and sentences in Mandarin Chinese.
Simplified Characters are on the left, and Traditional characters are on the right.
The pronunciation is given in the pinyin system, which may not always be as simple as it looks for those who have not studied it.
The Traditional Characters are now used in Hong Kong and Taiwan.
Chinese from Mainland China uses the Simplified Characters, but may recognize Traditional Characters.
Before 1956, Chinese was written using only Traditional Characters.
At that time most Chinese people could not read or write at all.
The government of the People's Republic of China thought that the Traditional characters were very hard to understand.
They also thought that if they made the characters simpler more people could learn how to read and write.
Today, many people in China can read and write with the new Simplified Characters.
Chinese Flashcard Website Learn Chinese Online
I Love Chinese Learning Chinese Magazine
Learn Chinese Free Chinese Learning Lessons and mp3
Free Chinese Character Input Software  Google Pinyin Input Software
Chinese Pinyin  a brief introduction to standard Chinese phonetic system
Day Day Up Chinese Online Chinese textbook
Direct method of learning Chinese—no English translation.
A wok is just a wok.
Study More Chinese  social network for Mandarin learners with videos, blogs, forum.
iChineseLearning A site for learning Chinese through skype Chinese lessons.
yimusanfendi Fact About yimusanfendi
Tonal languages
Zero (0) is a special number.
If there are zero things, then there is nothing at all.