The name "Europa" was later used to describe Greece. Then, as the rest of modern-day Europe started to have cities and empires, the entire area West of the Ural Mountains came to be called "Europa".
The history of Europe is long and has many turns. Many great countries originated from Europe. Greek mythology and the beginning of western civilization came from European nations.
Some of the major periods in European history have been:
Andreas M. Kaplan describes modern Europe as a continent where many different cultures live closely together, "embracing maximum cultural diversity at minimal geographical distances".
There are several major regions of Europe:
Within these regions, there are up to 48 independent European countries (with the identities of 5 transcontinental countries being disputed). The largest is the Russian Federation, which covers 39% of Europe.
The European city with the largest population is Istanbul. The country with the largest population is the Russian Federation. About 15% of Europeans live in Russia.
Two European countries, the United Kingdom and the Republic of Ireland, are on islands called the British Isles.
Most of Europe lies in temperate climate zones.
However, there are many different climates throughout Europe. For example, during the winter, it may be snowing and -30 degrees Celsius for 4–5 months in Finland. Yet it may be much warmer, with no snow at all except on high mountains, in Spain.
The European Union is a confederation of 27 European countries. These countries agree to follow common laws so that their citizens can move and trade in EU countries almost the same as they do in their own. Nineteen of these countries also share the same type of money: the euro.
Encyclopedia
An encyclopedia or encyclopaedia is a collection (usually a book) of information. Some are called "encyclopedic dictionaries".
All encyclopedias were printed, until the late 20th century when some were on CDs and the Internet. 21st century encyclopedias are mostly online by Internet.
The largest encyclopedia in the English language is English Wikipedia, which has more than 6 million articles. The second largest is the "Encyclopædia Britannica", which is the largest one that is printed. Either kind of encyclopedia can inform us on many different topics.
Book series were used to summarize all knowledge have been published for thousands of years. A famous early one was the "Natural History" by Pliny the Elder. The name "encyclopedia" is from the 16th century and meant "complete knowledge". The French "Encyclopédie" of Denis Diderot was the first that had major parts written by many people from all around the world.
After the printing press was invented, dictionaries with long definitions began to be called encyclopedias that were books that has articles or subjects For example, a dictionary of science, if it included essays or paragraphs, it was thought of as an encyclopedia or knowledgeable book on the subject of science. Some encyclopedias then put essays on more than one subject in alphabetical order instead of grouping them together by subject. The word, encyclopedia, was put in the title of some encyclopedias.
Companies such as "Britannica" were started for the purpose of publishing encyclopedias for sale to individuals, and for public use in libraries. Like dictionaries (which had definitions), these publishers hired hundreds of experts to write articles and read and choose articles. Some internet encyclopedias allowed their paying customers to submit articles from other encyclopedias. Other internet encyclopedias accepted writing from non-paying users (users who did not sign in) of the encyclopedia.
There are different types of encyclopedias. Some are general and have pages on lots of topics. The English language "Encyclopædia Britannica" and German "Brockhaus" are general encyclopedias. Some are about specific topics. For example, there are encyclopedias of medicine or philosophy. Others include the "Dictionary of National Biography", the "Dictionary of American Naval Fighting Ships", and "Black's Law Dictionary". There are also encyclopedias that that cover many topics with one perspective or one cultural bias. They include the "Great Soviet Encyclopedia" and Conservapedia.
There are two main ways of organizing printed encyclopedias: from A to Z (the alphabetical way) or by categories. Most encyclopedias go from A to Z.
Many dictionaries have similar information to encyclopedias.
Earth science
Earth science is an all-embracing term for the sciences related to the planet Earth. Earth science may also be called geoscience. Geoscience is the study of the architecture of the earth.
It is a broader term than geology because it includes aspects of planetary science, which is part of astronomy. The Earth sciences include the study of the atmosphere, oceans and biosphere, as well as the solid earth. Typically Earth scientists will use tools from physics, chemistry, biology, chronology and mathematics to understand the Earth, and how it evolved to its current state.
If there is one fact which underlies all Earth science it is this; the Earth is an ancient planet which has been changing the whole time since its formation. The extent of the changes is much greater than people used to think.
The following disciplines are generally recognised as being within the geosciences:
Earth
Earth is the third planet from the Sun. It is the only planet known to have life on it. The Earth formed around 4.5 billion years ago. It is one of four rocky planets on the inside of the Solar System. The other three are Mercury, Venus, and Mars.
The large mass of the Sun keeps the Earth in orbit, just as the mass of Earth keeps the moon moving around it. Earth also turns around in space, so that different parts face the Sun at different times. Earth goes around the Sun once (one year) for every 365 times it turns around (one day).
Earth is the only planet in the Solar System that has a large amount of liquid water. About 74% of the surface of Earth is covered by liquid or frozen water. Because of this, people sometimes call it the blue planet.
Because of its water, Earth is home to millions of species of plants and animals which require water to survive. The things that live on Earth have changed its surface greatly. For example, early cyanobacteria changed the air and gave it oxygen. The living part of Earth's surface is called the "biosphere".
Earth is part of the eight planets and many thousands of small bodies that move around the Sun as its solar system. The Solar System is moving through the Orion Arm of the Milky Way galaxy now, and will be for about the next 10,000 years.
Earth is about away from the Sun (this distance is called an "Astronomical Unit"). It moves on its orbit at an average speed of about . Earth turns all the way around about 365 times in the time it takes for Earth to go all the way around the Sun. To make up this extra bit of a day every year, an additional day is used every four years. This is named a "leap year".
The Moon goes around Earth at an average distance of . It is locked to Earth, so that it always has the same half facing Earth; the other half is called the "dark side of the moon". It takes about 27 days for the Moon to go all the way around Earth, but because Earth is moving around the Sun at the same time, it takes about 29 days for the Moon to go from dark to bright to dark again. This is where the word "month" came from, even though most months now have 30 or 31 days.
Earth and the other planets formed about 4.6 billion years ago. They were made of the leftover gas from the nebula that made the Sun. The Moon may have been formed after a collision between the early Earth and a smaller planet (sometimes called "Theia"). Scientists believe that parts of both planets broke off — becoming (by gravity) the Moon.