cahya/simple-wikipedia huggingface dataset:
Breakfast is the first meal of the day. It is usually eaten in the morning. The word comes from two other words; "break" ("end") and fast ("not eating for a long time").

Definition: [1463] from break (v.) + fast (n.). Cf. Fr. déjeuner "to breakfast," from L. dis-jejunare "to break the fast."

People around the world eat different things for breakfast:

 In the United States, people usually eat pancakes, waffles, toast, eggs or bagels for breakfast.
 In Canada, people usually eat maple cured bacon, fried potatoes, maple-infused beans, eggs, toast, pancakes and maple syrup or hot oatmeal for breakfast.

 In the United Kingdom a large breakfast was often, and still is sometimes, served. Usually this would be bread, tea, egg, bacon, ham, fruits, baked beans on toast and sometimes vegetables. This pattern of heavy eating has greatly changed in recent years. Most people do not do manual work nowadays.
 In France, people usually eat a very light meal; often bread and coffee with milk. Again, this depends on what kind of work is done (usually by the father of the household).
 In Asia, most people eat rice instead of bread. They also sometimes eat porridge.

References

Related pages 
Bacon and eggs
Diet (nutrition)

Meals
Condensed matter physics is a branch of physics which talks about matter that has its molecules packed together very closely. This usually means it deals with solids (solid matter).

Matter
Basic physics ideas
A bag is a kind of soft container. It can hold or carry things. It may be made from cloth, leather, plastic, or paper. Many bags are disposable but some are made to use for a long time. A bag may have one or two handles or a shoulder strap. Bags come in different shapes and sizes depending on how they will be used. A small bag that can be carried with a single hand is sometimes called a handbag, purse, or pocketbook.  Children can suffocate, or stop breathing and die, when they put certain kinds of bags over their heads, due to having the supply of oxygen cut off.

Other websites

Basic English 850 words
Containers
is the capital city of Hokkaidō Prefecture in Japan. The port city is on the southwest part of the island of Hokkaidō and it is the island's largest city.

The city has a famous snow festival in winter, it has a growing population of about 1,800,000 people.  Its area is . There are a lot of fish markets in Sapporo. A beer brand named "Sapporo" was named after this city. Ramen is a very popular food in Sapporo. The city has a subway system. Some famous landmarks are the Sapporo TV Tower, and the clock tower that is in the center of the city. There are several universities here, including Hokkaido University. The nearby airport is called New Chitose Airport.

Events
1972 - The Winter Olympic Games were held in Sapporo.

Related pages
 Consadole Sapporo

References

Other websites

 City of Sapporo
 Sightseeing of Sapporo 
 Sightseeing of Sapporo

Olympic cities
is a special Japanese prefecture in Hokkaidō region on the island Hokkaidō.  It is the most northern prefecture of Japan.

Sapporo is the capital city of Hokkiado.

History

Until the Meiji Restoration, the island was called Ezo, Watari-shima, Yeddo, and Yezo.  Since 1869, it has been called Hokkaidō.

The population expanded in the late 19th century.

Timeline
 1947 (Shōwa 22): Hokkaidō Prefecture was established.

 2008 (Heisei 20): 34th G8 summit at Toyako

Geography
Hokkaidō is the 2nd largest island of Japan The island is between the Sea of Japan to the west, the Sea of Okhotsk to the northeast, the Pacific Ocean to the southeast, and the Tsugaru Strait to the south. 

Hokkaidō is separated from Honshu by the Tsugaru Strait; however, it is connected by the underwater Seikan tunnel.

Some of the Chishima Islands are occupied by Russia, but Japan still considers the islands to be Japanese.

National Parks
Natural Parks are established in about 10% of the total land area of the prefecture.

Shrines and Temples
Hokkaidō jingū was the chief Shinto shrine (ichinomiya) of Ezo, which was an ancient name for the Hokkaidō region.

Related pages
 Provinces of Japan
 Prefectures of Japan
 List of regions of Japan
 List of islands of Japan
 Consadole Sapporo

References

Other websites 

  Murdoch's map of provinces, 1903
Color coding for atomic numbers:
 Elements numbered in blue are liquids at Standard Temperature and Pressure (STP);
 those in green are gases at STP;
 those in black are solid at STP;
 those in red are synthetic (all are solid at STP).
 those in gray have not yet been discovered (they also have muted filled colors indicating the likely chemical series they would fall under).

Related pages 
 Periodic table

Periodic table
The medlar is a tree and the name of the fruit of this tree. Its Latin name is Crataegus germanica, or "German medlar", but it is not from Germany. It grows in the Near East and South-Eastern Europe, and the Romans took it to Germany. Near the Caspian Sea, people grew the medlar about three thousand years ago. It came to Greece in about 700 BC and to Rome in about 200 BC. It was an important fruit plant in Roman and medieval times. But by 1600-1700, people started eating other fruits and not the medlar. Today people do not grow it very often.

The medlar needs warm summers and mild (not too cold) winters and likes to grow in sunny, dry places. In the best places, the plant can grow up to eight metres tall. The medlar is deciduous: it is not green all year. Usually, it is shorter than a tree. It lives between thirty and fifty years. Medlar leaves are dark green, maximum fifteen centimetres long and three centimetres wide. The plant has flowers in late spring. The flowers are white. The red-brown medlar fruits are similar to apples and grow to two to three centimetres. They are very hard and acidic, and we can only eat them after the cold weather makes them soft.

Other websites

Fruits
Amygdaloideae
Hippocrates (c. 460 – c. 370 BC) was a Greek doctor who is called the "father of medicine". He was the first person to teach that people got sick for scientific reasons. Previously, people believed that disease was caused by angry gods.

Many of Hippocrates' writings are still important to doctors. For example, patient confidentiality, meaning that doctors can only discuss a patient with the patient themselves. Another of his ideas is to never knowingly lead a patient to suffering or death. These kinds of ideas are part of medical ethics.

The Hippocratic Oath is named after him. This is a set of rules which doctors promise to obey. This is an example of a modern Hippocratic Oath used at the University of North Carolina School of Medicine. I do solemnly swear by all I hold most sacred:
 that I will be loyal to the profession of medicine and just to its members
 that I will lead my life and practice my art with virtue and honor
 that into whatsoever home I shall enter it shall be for the good of the sick and the well by the utmost of my power and that I will hold myself aloof from wrong and from corruption and from the tempting of others to vice
 that I will exercise my art solely for the benefit of my patients, the relief of suffering, the prevention of disease and promotion of health, and I will give no drug and perform no act for an immoral purpose
 that in the treatment of the sick, I will consider their well-being to be of a greater importance than their ability to compensate my services
 that what I may see or hear in the course of treatment or even outside the treatment in regard to the lives of persons which is not fitting to be spoken, I will keep inviolably secret
 that I will commit myself to a lifetime of continued learning of the art and science of medicine
 these things I do promise and in proportion as I am faithful to this oath, may happiness and good repute be ever mine, but should I trespass and violate this oath, may the reverse be my lot.

References 

460s BC births
4th-century BC deaths
Greek physicians
Ancient Greek philosophers
History of medicine
Commensurability is a concept in the philosophy of science. Scientific theories are described as commensurable if one can compare them to find out which is more accurate. If there is  no way  one can compare them to determine which is more accurate, they are incommensurable.

Behind this is the idea that it is possible to see the world in multiple ways, and that there is not one fair method to see which way is right. Some think that scientific traditions (or paradigms) can be incommensurable: it is not really possible to say which one is right. This idea has been defended by Thomas Kuhn. He wrote: when paradigms change, the world changes with them. Paul Feyerabend was another philosopher who said that incommensurability was possible in scientific topics. He wrote that it is important to remember this, because it means that it is possible to say things that are not scientific, but also not wrong. These ideas were mainly aimed at Karl Popper and his ideas on falsification.

Two theories may not be comparable if one cannot find a way to compare them and decide which is right.

In popular culture
The concept of incommensurability is dramatized in the 2006 movie Idiocracy, when U.S. Army scientist Joe Bauers attempts to explain before a full Cabinet meeting his theory that the nation's crops would be better irrigated with water rather than with a sports drink.

References

Philosophy of science
ELISPOT stands for "Enzyme-Linked Immunosorbent Spot Assay".  It is a laboratory technique for detecting cells that make (or "secrete") various substances.  These substances include specific types of cytokines or antibodies.  The ELISPOT method is typically used with blood cells, and is a helpful tool in studying the human immune system and various treatments for disease (e.g. vaccines).

In the ELISPOT technique, tiny wells are used to contain the cells, with a variety of other substances.  The substances cause colored spots to form near the cells that secrete the substances in question. These spots can then be counted manually (using a microscope, for example) or automatically using specialized equipment with computer vision capabilities.

The ELISPOT technique is very sensitive, and can detect even a single substance-producing cell. It is also very versatile, since it can be tailored to detect a wide variety of very specific secretions.

Other websites 
A flash animation of the ELISpot procedure 
An animated illustration of the ELISPOT process 
 Examples of spot patterns formed by the ELISPOT technique

Biochemistry
This is a list of all the articles related to biochemistry.



A 
abiogenesis - adenine - adenosine diphosphate (ADP) - adenosine triphosphate (ATP) - albumin - allotrope - alpha helix - amino acid - amylase - antibiotic - antibody - antigen -

B 
B vitamin complex - base pair - bilirubin - benzene - biochemistry - bioluminescence - blood - blood type

C 
carbohydrate - carbon dioxide - catabolism - cell - cell membrane - cellobiose - cellular respiration - cellulose - chemoautotroph - chloroplast - choline - chromatography - citric acid - coenzyme A - cytoplasm - cytokine - cytosine - cytosol -

D 
deoxyribose - disaccharide - DNA - DNA replication -

E 
ELISA - ELISPOT - energy level - enkephalin - enzyme - epinephrine - erythropoietin -

F 
fat - formaldehyde -

G 
gel electrophoresis - glycolysis - glycoprotein -  granzyme - guanine -

H 
hemoglobin - hormone - hydrocarbon - hydrogen bond - hydrolysis -

I 
immunoglobulin - immunology - insulin - intermolecular force - ion channel - ionic bond - isomer -

K 
keratin - kinetic energy - Krebs cycle -

L 
Le Chatelier's principle - light-dependent reactions - light-independent reactions - Link reaction - lipid -

M 
macromolecule - membrane protein - metabolism - microbiology - molecular biology - molecule - monosaccharide -

N 
NADPH - neurotransmitter - niacin - nicotinamide adenine dinucleotide phosphate - Nobel Prize in Chemistry - nucleic acid - nucleobase - nucleotide - nutrient - nutrition -

O 
organic chemistry - organic compound - osmosis - oxidation -

P 
peptide - pesticide - pH - photosynthesis -  physiology - polymer - polysaccharide - potential energy - prion - protein - protein biosynthesis -

R 
redox - respiration (physiology) - riboflavin - ribose - ribosome - RNA -

S 
saturated fat - scientific notation - sequence analysis - signal transduction -  solvation - starch - substrate (biochemistry) - sugar - synapse

T 
T cell - thymine - toxin - trans fat - transcription (genetics) - translation (genetics) -

U 
unsaturated fat - uracil -

V 
vaccine - virus - vitamin - Vitamin A - Vitamin C - Vitamin D - Vitamin E - Vitamin K -

Y 
yeast -

Chemistry lists
Billion is a name for a large number. It may refer specifically to:

 1,000,000,000 (, one thousand million), the short scale definition now normal in both British and American English
 1,000,000,000,000 (, one million million), the long scale definition used formerly in Britain and currently in certain other languages

Billion may also refer to: 
 Billions (TV series), a Showtime series
 Billions (movie), a 1920 silent comedy
 Billion (company), a Taiwanese modem manufacturer
 Jack Billion (born 1939), 2006 Democratic Party candidate for governor of South Dakota
 Mr. Billion, a 1977 movie by Jonathan Kaplan
 "Billions" (song), a song on Russell Dickerson's album Yours
The job of white blood cells (also called leukocytes) is to fight infections and cancer. They also remove poison, waste and damaged cells from the body.

The number of white blood cells increases when a person is fighting infection or disease and decrease when a person is healthy.

Types of white blood cells

Lymphocytes 
Lymphocytes are round white blood cells a bit bigger than a red blood cell. Their center is round and they have little cytoplasm. Part of the lymphatic system, these target specific germs or poisons using their antibodies. There are three known types of lymphocytes, called T-cells, B-cells, and natural killer cells (NK cells).

B-cells make antibodies, which are little molecules that attach to viruses or bad cells. These tell other cells to destroy the viruses or bad cells, like a flag.

T-cells can either help make more B-cells, or kill cells with antibodies.

Natural killer cells kill cells in the body that have been infected by a virus or that are part of a tumor. They are part of the innate immune system.

Monocytes 
Monocytes are reserve cells which turn into macrophages and dendritic cells, which work together in tissues to fight disease. Monocytes have a kidney bean shaped center and lots of cytoplasm. They may appear as macrophages in a non-round shape when they pass through tissue to eat germs, "junk" cells, and dead cells.

Granulocytes 
The next three types of white blood cells are referred to as granulocytes since they all contain rough, grain-like particles that assist in attacking viruses and bacteria. Granulocytes are also called polymorphonuclear leukocytes because of the shape of the nucleus, which has three segments.

Neutrophils 
Neutrophils are the most abundant type of white blood cells in mammals, 70% of leukocytes. They are an essential part of the immune system. They get to the site of an injury within minutes, and make up much of the content of pus. They have a short life-span of a couple of days.

The nucleus, which looks like a string of beads, does not take up stain strongly. Like phagocytes, they actually eat the bacteria and dead cells. They also release a bunch of proteins which work to damage the bacteria.

Basophils 

Basophils, or basophil granulocytes, are rare granulocytes. If you collected 1000 white blood cells, only 13 of them would be basophils. Their nucleus is hidden by granules which turn dark blue in color when stained. Basophils carry histamine and heparin. They appear at the sites of ectoparasite infection, or allergies. We don't know exactly how they work.

Eosinophils 
Eosinophils, or acidophils, are leukocytes. They are one of the immune system components which combat parasites and certain infections. As with mast cells and basophils, they part causes of allergy and asthma. Eosinophils are round cells with a lobed nucleus and granules which turn red when stained. These granules are packed with proteins that can be poured out to help destroy invaders.

Cell testing 
A test called a differential count shows how many white blood cells there are in a person's blood, and how many of each type are there.

References 

Cell biology
Immunology
An author is a person who writes  books, stories, poems, or other written work.  Their writing can be truth or fiction, short or long.  Often, author is a word for a professional writer, but any person who writes may also be called that.

Sometimes, a person who creates something that is not prose is called an author. Someone who writes music may be called the author of that piece of music, though we would usually call that person a composer. In the film world, the French word for author, auteur, is often used about someone who has been both the writer and director of a movie. 

In biology, the first person to write an article that gives a name to and describes a type of living thing is the author of that name. 

In copyright law, the author is the first owner of copyright.  Such laws also apply to other works of art such as pictures or music.

Related pages 
 Writer
 Journalist

References

Other websites 
 Networks of scientific papers
Pedipalps are the two appendages on the front of a spider's head. Some spiders seem to have ten legs and not eight, because these pedipalps look like an extra pair of legs. The pedipalps are used rather like arms.  Spiders often use them to hold insects (for example crickets) for them to eat.

Male spiders also use pedipalps for mating.  The male spiders make some silk, put sperm onto the silk, and then put their pedipalps into the sperm.  The pedipalps then hold the sperm, and the spider can use it to mate with a female by putting them inside her epigynum.

Diversity of pedipalps 
The pedipalps of all chelicerates vary: Ricinulei, Thelyphonida, Amblypygi, some Opiliones, Schizomida, Scorpions and pseudoscorpions all have theirs as pincers, with the Amblypygi's being their entire pedipalps shaped like mantids. The Palpigradi's pedipalps have some of the strangest roles of arachnids as they use theirs for locomotion. The pedipalps of Solifugae act as antenna.

Other websites 
 Close-up view of pedipalps on a large spider 

Animal anatomy
Arachnids
In chemistry, an ionic compound is a compound made of ions. They have strong ionic bonds between particles. Lots of energy (heat) is required to break the bond apart, resulting in high melting and boiling points. The ions join together because they have different charges. Compounds of metals and non-metals are usually ionic. They are made when two or more atoms come close together and an electron goes from one atom to the other atom. The electron does this because both atoms want a full outer shell, similar to those of the noble gases.

Note 1: carbon and silicon in Group 4 usually form covalent bonds by sharing electrons.

Note 2: the elements in Group 0 do not react with other elements to form ions

Physical properties

Chemistry

sv:Jonförening
The ELISA method (Enzyme Linked Immuno-Sorbent Assay) is a technique used in biochemistry to determine if a certain substance--such as a specific cytokine or antigen--is present within a sample. It is sometimes abbreviated as "EIA."

This technique uses special antibodies that attach themselves to the substance. These antibodies generate a specific color. The amount of color indicates the amount of substance present. (Sometimes, the substance must be viewed under ultraviolet light for the antibodies to generate this color.)

Another set of antibodies are used to "capture" the substance. These antibodies adhere to both the substance and the testing container, thus holding the substance in place.

A more sophisticated and sensitive technique, the ELISPOT method, was derived from the ELISA techique.

Other websites 
 An animated illustration of an ELISA assay 
 Image of a microtiter plate, such as is commonly used in ELISA tests

Biochemistry
David Hume (7 May 1711 – 25 August 1776) was a philosopher and historian from Scotland. When he was still alive, people thought of him as a historian. He wrote a series of large books called The History of England. But today, people think of Hume as an important philosopher.

Works
In his books on philosophy, Hume said that many of our beliefs do not come from reason. Instead, they come from our instincts or feelings. For example, reason does not tell us that one thing causes another. Instead, we see one thing and then we see another, and we feel a link between the two. Similarly, reason does not tell us that someone is a good person. Instead, we see that the person is kind and friendly, and we feel a special moral feeling. Because Hume thought that these beliefs do not come from reason, people call him a "skeptical" or "anti-rationalist" philosopher.

Hume is famous for his 'Induction Fallacy'. This draws attention to a common mistake people make. People see something, and make claims that what they see will always be as they see it. For example, people see only white swans and claim that all swans are white. This is 'fallacious' or mistaken, because it is always possible that they then will see a black swan.

Hume was also skeptical about religion. He was not a religious person and religious people did not like his opinions. He did not believe in miracles. He said that suicide wasn't always wrong, but never said whether or not he believed in God. In 1776, when he was dying, his friends found him very calm about death, despite him not believing in an Afterlife. Today, Hume's books are very important to philosophers who are interested in religion.

Influence
Today's philosophers sometimes use the term 'Hume's fork' to refer to Hume calling everything we can think about either a relation of ideas (things like mathematics, that must be true) or a matter of fact (like science, where we have to look at things to tell whether or not they are true).

Another philosopher, Immanuel Kant, read some of Hume's books and changed his mind about some important things. Kant said Hume had made him wake up from a sleeping dogmatism, the traditional metaphysics.

Books
Here are Hume's most important books:

 A Treatise of Human Nature: Being an Attempt to introduce the experimental Method of Reasoning into Moral Subjects. (1739-40)
In this large book, Hume talks about the human mind and tries to figure out how it works. He talks about knowledge, cause and effect, emotions, right and wrong, and many other things.

 An Enquiry Concerning Human Understanding (1748) 
In this small book, Hume talks about many of the same things from the Treatise, like knowledge and cause and effect. He tried to make this book easy to read.

 An Enquiry Concerning the Principles of Morals (1751)
This is another small book, and again, Hume tried to make it easy to read. The book is about right and wrong.

 Dialogues Concerning Natural Religion (after Hume died)
In this book, Hume has three characters who argue with each other about God.

References 

1711 births
1776 deaths
People from Edinburgh
18th-century British philosophers
A bath (UK English) or bathtub (US English) is a basin large enough for people sit in when washing their body.  The bath is usually in the bathroom.  A less common name for a bath is a washtub.

Sometimes people will add scents, oils and salts to the bath for better experience.

A bath is also a place where people can sit in water (or other liquids, often hot) for their health. This is where the town name Bath comes from. Public baths for relaxing were built in all parts of the Roman Empire.

Other 
 Bird bath
 Bathhouse
Steam bath

Home
Hygiene
A brush is a tool with bristles or wires or other filaments sticking out. There are many kinds. Most brushes have a long part at one end to hold (the handle), on the other end from the head that carries the bristles or filaments. We use brushes for cleaning, making hair look good, painting, and other purposes.

Brushes for cleaning

Many kinds of brushes are made for cleaning, for example toothbrushes or brushes for cleaning floors.

Paint brushes
We use paint brushes for putting ink or paint on paper. If a brush is dipped 1/3 to 1/4 of it’s length into a can of paint, a good brush will ideally pick up the perfect amount of paint and spread it on a surface in a film that is smooth and uniform and absent of any drips, dips, or brush marks. Paint brushes typically come in two forms, synthetic, and natural. Synthetic brushes are usually made from products such as nylon, while natural refers to bristles from an animal source. Computer graphics uses digital paintbrushes for making pictures.

Paint brushes can have three shapes:
 Round: The long, close-together bristles of these brushes mean they can hold more paint. This is why many artists like them for painting large things and for color washes.
 Flat: These are good for spreading paint.
 Fan-shaped: These mix paint well.

Brush care 
 Clean paint from brushes after you use them. This is very important for oil and acrylic paint because when the paint is dry, taking it off can break the brush.

 Never leave brushes in water (etc.) with the bristle end down. This is because the bristles can change shape.

Sizes and materials 
We can buy brushes in different sizes and materials. Here are some sorts.

Decorators' brushes 
The sizes of brushes used for painting and decorating (changing the colour or look of a room) are usually in millimeters or inches. This shows how wide the head is. 

Here are some sizes:

 1/8", 1/4", 3/8", 1/2", 5/8", 3/4", 7/8", 1", 1¼", 1½", 2", 2½", 3", 3½", 4".

 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm.

We can buy brushes with natural or synthetic (man-made) bristles. Handles (the part of the brush we hold) may be wood or plastic.

Artists' brushes 
Artists' brushes usually have sizes with numbers, but there is no standard.

From smallest to largest, the sizes are: 

 7/0 (also  0000000), 6/0, 5/0, 4/0, 000, 00, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 20, 22, 24, 25, 26, 28, 30.

We use sizes 000 to 20 most often.

Bristles may be natural -- either soft hair or hog (pig) bristle -- or synthetic (man-made).

Artists' brush handles (the part of the brush we hold) are often wooden, but the cheapest brushes may have plastic handles. Many cheap handles are made of unfinished wood; better quality handles are of finished wood.

References 

Basic English 850 words
Tools
Starch is a complex carbohydrate. It is made of many glucose units joined by chemical bonds. This polysaccharide is produced by most green plants as an energy store. It is the most common carbohydrate in human diets. Pasta, potatoes, bread, and other starchy foods are made out of carbohydrates.

Starch in every day activities.

Starch in food 
Some good food sources of starch are cereals, bread, potatoes, grains, peas, and beans. Starch is also used for thickening sauces in cooking and thickening cold foods during a preheat. Starch is a white powder that is tasteless and odourless. Corn starch or cornflour is known as a popular kind of starch made from corn.

Foods with a lot of starch produce more energy than other foods. However, if this energy is not used, it is turned into fat by the liver through de novo lipogenesis.

Laundry starch 
There are also different kinds of starch, like laundry starch, which gives clothing a smooth and crisp feel. Sweat and dirt from a person’s wrist and neck will stick to the starch on the clothes, not to the fibers of the clothes, and will wash away along with the starch. Then, after each laundry load, the starch can be used again.

Other facts 
Starch glues are used in wood, cotton, and bonding of paper. Animals and humans have amylase, so they can digest starch.
Starch was used in Europe in the 16th and 17th centuries to stiffen the collars and ruffs of the fine linen which surrounded the neck. Starch also requires heat to thicken. The actual temperature depends on the type of starch.

Carbohydrates
Thomas Hobbes (5 April 1588 – 4 December 1679) was a philosopher from England. His most famous book is Leviathan (1651).

Writings
Hobbes mainly wrote about government and law—he was a political philosopher. He tried to show that the best kind of government has one in which society was organised under one authority. All individuals in that society give up some rights for the sake of protection. There is no doctrine of "separation of powers" in Hobbes's discussion. According to him, the sovereign power must control civil, military, judicial, and ecclesiastical powers.

Studies
Looking at human nature, we will see that humans are very selfish and that we are willing to hurt each other if we think it will help us. Naturally, humans are all equal because we are all strong enough to kill each other—even a child can kill a strong man while he sleeps. Imagine what things would be like without a government. It would be terrible—a "state of war". There would not be enough stuff for everyone, and people would disagree about who got what. Some people would fight each other, and everyone else would be very worried about their own safety. No one would be able to trust anyone else or make plans for the future. Life would be "solitary, poor, nasty, brutish, and short" (people would be alone, poor, mean, and would not live for long). Next, Hobbes argues that it would be a good idea for everyone to stop fighting and choose a Sovereign which could be one man or an assembly of men. Everyone should agree to obey the Sovereign, and give him all power of coercion or force of restraint under law. Once the Sovereign is in place, everyone has to obey him, even those who disagree with him. This is because everyone already agreed to obey him no matter what. Hobbes says it's better to be mostly safe under an all-powerful Sovereign, than to be in a state of war.

Hobbes wanted his argument to be like math, with each step leading to the next. However, many people disagreed with his argument. Some said that Hobbes was in favor of rebellion, because he said that people were naturally equal. Others said that humans are not as selfish as Hobbes thought. Today, most people do not like the idea of an all-powerful government. Nevertheless, Hobbes's argument was a very important one, and philosophers who are interested in government or political theory still study Hobbes's books very carefully.

References 

1588 births
1679 deaths
17th-century English philosophers
Nicomachos or Nicomachus is a Greek name. It can mean:
Nicomachus of Gerasa, an ancient mathematician

Nicomachus, the father of Aristotle and court physician (doctor) to King Amyntas III of Macedon. Nicomachus died when Aristotle was about 10. Nicomachus wanted Aristotle to follow in his footsteps. But Aristotle did not become a doctor but a philosopher.

Given names
A logo is a picture or drawing that is used by a person, group, or company to mark who they are. A wordmark, or 'logotype', is a logo made entirely of a word or words. It is usually the name of a product or organisation.

A company or group can use a 'logo' on the things that they make, like on the things they sell, on letters, and in advertisements. When a person sees the logo picture, that person knows that the thing they see the logo on came from that company.

Logos can have letters and words in them. Many logos have the name of the company or group in them.

Most logos are very simple drawings with only a small number of colors. Some logos are only in black and white.

In many countries, companies and groups should tell their country's government about the logo they are using. If they do this, the government can help stop a different company or group from using the same logo, so that every one can be sure that the logo is only used by the people who used it first. This is sometimes called a 'trade mark'.

Logos are not used only by companies. Many schools have logos. Some cities have logos. Clubs can have logos. Even people can have their own logos if they want. The heraldic badge is probably the oldest form of logo in the world.

References

Related pages 
Logogram

Symbols
A picture, also called an image, is a group of coloured points on a flat surface that looks the same as something else. For example, a picture can look the same as an object or a person. Pictures can also be drawings, paintings or photographs. People who make such pictures are called artists, photographers or painters.  Pictures are very helpful.  Sometimes people say pictures are worth a thousand words.  Pictures and diagrams can be used to explain how to do things, and thus a picture is a kind of tool. A moment captured in an image.

An image is something that can be seen, but it is not physically there.  It can be a photograph, a painting, or a picture on a television or computer screen.  A lens can make an image of an object appear somewhere else.  Cameras use this to make the image that becomes a photograph.

Making Pictures

Most pictures today are 'photographs'. Photographs are made with cameras. A camera makes a picture that looks very real.

When there were no cameras, people made pictures by using paint, brushes, pencils, crayons, pens, and other things that people can write or draw with. Pictures made with paint and brush are called 'paintings'. Before cameras, some artists were able to make very real looking pictures with just paint. Sometimes pictures made with pencil or pen are called 'sketches', if they are made quickly and only look a little bit like the real thing.

Usually pictures are put on paper. Pictures made with paint are usually put on a strong, rough fabric called 'canvas'. Sometimes pictures can be put on walls or other things, even glass.

Some places, such as churches have pictures on windows made out of colored pieces of glass. These are called stained glass.

Special types of Pictures 

If people take a lot of pictures, and show them one at a time, very fast, they can make a picture that looks like it is moving.  This is called a "moving picture", or a movie.  A television shows people a moving picture by using light. 

A slide show is a series of pictures arranged to tell a story, for example to illustrate a narrative.  

A projector shines light from a light bulb through a kind of transparent picture.  When light shines through this kind of picture onto a screen or another flat place, the picture can be seen on that flat place.  This is often used to show movies and slide shows to an audience.

Some people make pictures that do not look flat, by taking two regular flat pictures at the same time. People have to move their eyes in a special way or use a stereoscope so they can see both pictures together.  When they look at the pictures using their binocular vision correctly, the picture does not look flat.  This is called '3D' or 'three dimensional'.

Cutaway pictures show what is inside of something, that cannot actually be seen.

Graphics
A candle is a stick made of wax with a string (a thin piece of rope) straight in the middle. If someone puts the string on fire, the flame burns slowly but for a long time.

Fire can burn string very fast. But in a candle, the string does not burn fast, because the fire melts the wax instead. The wax sometimes drips down the side of the candle. When the melted wax is far from the flame, it gets hard again, and can be used again in a new candle. 
 
The flame is very hot, since it is a very small, real fire. The light blue part of the flame can be as hot as . It can still burn people and things. If the fire spreads, it can grow into a very big fire and even burn down a house or building. 

If the flame is kept on the candle long enough, the candle will slowly get shorter and shorter until it is gone. The fire on a candle can be put out by blowing air on it. There is also a special tool called a "candle snuffer" that covers the fire with a small metal cup and puts it out. Today, candle snuffers are usually only used in churches or in places where candles are up very high. Stopping the fire stops the candle from burning until it is all gone.

Before light bulbs, candles were used so people could see at night. Some people still use candles today when electricity is down, or because they like the little amount of light that candles make. Some people also like candles because they look nice, or because they smell nice. A special kind of candle called "citronella" can help keep bugs away.

Related pages
 Lantern
 Electric light
 Advent

References 

Light sources
Fire
Christian symbols
Newts or efts are small amphibia. They are in a subfamily of the salamanders. They are found in North America, Europe, and North Asia.

Life cycle 
Females lay eggs and leave them. Tadpoles are born from those eggs.

Newts have three life stages. First as a tiny aquatic larva, which gradually undergoes metamorphosis. Then they leave the water for a year as a juvenile called an eft. They go back in the water to breed as adults.

In some species the adults stay in water for the rest of their lives. Others are land-based, but return to water each year to breed.

Defences 
Many newts produce toxins in their skin secretions as a defence against predators. They have bright skin colours as a warning to other animals.

Taricha newts of western North America are particularly toxic; the rough-skinned newt Taricha granulosa of the Pacific Northwest produces more than enough tetrodotoxin to kill an adult human. Recently, a 29-year-old man in Coos Bay, Oregon, who had been drinking heavily, swallowed a rough-skin newt for a dare; he died later that day despite hospital treatment.

Most newts can be safely handled, provided that the toxins they produce are not ingested or allowed to come in contact with mucous membranes, or breaks in the skin. After handling, proper hand-washing techniques should be followed due to the risk from the toxins they produce and bacteria they carry, such as salmonella. It is illegal to handle or disturb great crested newts in the UK without a licence.

Are newts a related group? 
The term "newt" has traditionally been used as a functional term for salamanders living in water, and not a systematic unit. The relationship between the genera has been uncertain, though they may be a natural systematic unit. Newer molecular analysis tend to suggest they actually do form a clade.
Newts only appear in one subfamily of salamanders, the Pleurodelinae (of the family Salamandridae).
Some genera occasionally listed as Pleurodelinae are not newts (Salamandrina and Euproctus).

References 

 
Amphibians
Many animals develop in separate stages. A larva (plural: larvae) develops from the egg in those animals. It is a separate life stage from the adult reproductive stage. A larva does not look like the adult animal, and changes shape (known as metamorphosis) as it grows up. There may be several larval stages before the adult form. Tadpoles, maggots and caterpillars are larvae.

Marine organisms with a larval stage often release large numbers of eggs and sperms into the water column. After fertilisation, the eggs develop into tiny larvae. The larvae develop and grow for some time before metamorphosing into adults. Most marine invertebrates and many fish have a pelagic larval stage or pelagic eggs. These live in the plankton, and may be transported long distances.

Evolutionary theory 
Probably the most widely accepted theory explaining the evolution of larval stages is the need for dispersal. Sessile organisms such as barnacles and tunicates, and sea-floor groups like mussels and crabs, need some way to move their young into new territory, since they cannot move long distances as adults. Many species have relatively long pelagic larval stages (how long a larva is in the water column). During this time, larvae feed and grow, and many species move through several stages of development. For example, most barnacles moult through six nauplius larva stages before moulting to a cipris, when they look to settle. The larvae eat different food from the adults, and disperse.

The other consideration is the small size of the eggs. If animals lay many small eggs (and most do), then the young stages cannot live the life the adults lead. They must live a separate life until they have the size and capability to live as an adult. This is what the larvae do.

Origin of vertebrates 
A long-standing theory is that in transformed larvae of sea-squirts (tunicates) lies the origin of vertebrates. Tunicates are sessile, but their larvae are mobile, and have some features found in early vertebrates. The process of paedomorphosis, where juvenile features are retained in the adult, is the proposed mechanism. Genome analysis does show that the tunicates are the closest living relatives of vertebrates.

References 

Animals
Developmental biology
A father (also called dad or daddy) is a male parent. Most human beings are born from a mother and a father. The father of a person's husband or wife is their father-in-law. Fathers determine the gender of their child through a sperm cell which either contains an X chromosome (female), or Y chromosome (male).

Related pages
God the Father

Basic English 850 words
Family
Gills are what fish, amphibians, and some other animals use to breathe in water. They have feathery parts which cause water to move across the animal's body, which contains dissolved oxygen, after the animal has swallowed the water. The oxygen is absorbed into the animal's blood, causing carbon dioxide moves out of the animal's blood and into the water through the gills.

Fish and frog gills are hidden on the sides of their heads. Sharks have many gills slits on their necks. Baby salamanders have gills that stick out like leaves from their heads.

In mushrooms, gills are the spore-bearing structure in agarics (gilled mushrooms) while fish and some young amphibians use them to get oxygen others breath.

Some insects that live in water have a plastron, which is a kind of gill. It is a patch of special hairs that keeps the water away from the insect's spiracles. This allows them to continue to take in oxygen and remove carbon dioxide while they are under water.

 

Animal anatomy
Anatomy of the respiratory system
A chemical compound is a chemical formed from atoms of different chemical elements. The different atoms are joined by chemical bonds. Each compound has a fixed ratio between the elements (crystal)

The elements stick together so strongly that the compound behaves like one substance. The chemical that is made depends upon what atoms it is made of and how they are joined together.

Chemical compounds can be liquids, like water which is made from atoms of hydrogen and oxygen joining together. They can also be solids, like sodium chloride that contains sodium and chlorine atoms. We get compounds from natural sources such as plants or make them in laboratories. Compounds can be made from others by scientists and these are called synthetic chemicals.

When different compounds are mixed together they may have a chemical reaction. 
Some chemical compounds can be dangerous but are safe if they are used the right way. Most dangerous chemicals are only used by scientists who have had special training in how to handle and use them. These chemicals might be poisonous, corrosive, explosive, they may catch fire easily, or they may react with other substances.

People who work in factories near chemicals often wear special clothes that stop the chemicals from hurting their body.

References
Wood is the main substance in trees. It is mainly formed by the xylem vessels which carry water up the plant. The two main substances in wood are cellulose and lignin. Wood is used to make buildings and furniture, and also for art. Firewood is a fuel. Paper is made from wood fibres. Wood is a renewable resource although it has become scarcer in recent centuries.

Wood is hard to cut, but it is also strong. A lumberjack is a person who cuts down trees. After a tree falls, the wood in it can be cut into long, straight pieces called lumber. Lumber can then be used to make posts, or put together with nails, screws, or even glue to make wooden frames for other shapes.

Wood comes in many different kinds. Oak, maple (hardwood) and pine and redwood (softwood) are widely used types of wood. Woods are usually divided into softwood (from conifers) and hardwood from flowering plants.

Housing 
For a long time and even today, many buildings, mostly houses, have been made of wood. To build a house with wood, lumber is put together into frames that are the shape of each wall, floor, and roof of the house. Then the frames are placed into the shape of a house. Then the frames can be covered to make solid walls. Sometimes the walls are made of more wood.

When the outside of a house or building is covered in wood, the wooden pieces are usually flat and stacked. These pieces are called shingles. Wood is also sometimes used in other parts of the house, like doors and staircases. Wood is also used to make fences.

Carpentry 

Carpenters make houses of mostly soft wood such as pine. For many kinds of furniture they use harder wood such as maple or oak. When someone builds something with wood, they often paint it. Paint protects and beautifies the wood. Some people like the look of wood, so they put clear paint called varnish on it. This helps to protect the wood and gives it a shiny finish.

Some people make art with wood. Sometimes sculptures are built with wood: see Grinling Gibbons.

Regular pencils are made of wood. Inside is the "lead", which is not actually lead. Clay or wax and graphite form the "lead" in a pencil.

Paper 
Wood is turned into paper in large factories called paper mills.  Heat, chemicals and machines separate the cellulose fibers from other parts and press the fibers into paper.

Sources 
 Jane F.W. 1970. The structure of wood. 2nd ed, edited by K. Wilson & D.J.B. White. London: Adam & Charles Black.

Related pages 

 Tree
 Petrified wood
 Plywood
 Firewood

Other websites 
 Wood -Citizendium

Basic English 850 words
Chalk is a type of limestone. It was made by calcareous (CaCO3) skeletons of tiny planktonic algae called coccoliths. They live in the sea in huge numbers. They make chalk (CO2) as a by-product of their photosynthesis. The chalk cliffs of Dover and elsewhere were made when England was below the equator in a tropical sea. It was in the Upper Cretaceous, when the Earth was even warmer than now. There are coccoliths today, but not the same species as formed the white cliffs.

Air and water do not wear chalk away easily, so when chalk is next to the sea, it often makes a large cliff. The "White Cliffs of Dover" in Kent, England are a good example of this. Chalk holds water, so these chalk hills may have a lot of water in them. When the weather is very dry, water comes slowly from the chalk. 

Blackboard chalk is not real chalk. It is really gypsum (calcium sulfate), but people call it "chalk". People use it for drawing on hard things, because it is soft. If this chalk is rubbed on something hard or rough, it will leave a mark. People often write with chalk on a chalkboard or blackboard. A chalk eraser or water can be used to clean the chalk marks away so the board is clean again. Shops usually sell blackboard chalk in sticks that are about 5 cm long.

There are also big pieces of soft chalk for children to write on the ground with, for example on concrete (such as a sidewalk) or on asphalt. It is usually okay to write on the ground with this kind of chalk, because the rain will wash the chalk away.

Tailors' chalk is not real chalk either. It is talc (magnesium silicate). Tailors use it to draw on material when they are making clothes.

Basic English 850 words
Carbonate rocks
Writing tools
Cretaceous