The air usually always contains some water vapor.

Water has three phases: liquid water, solid ice and water vapor. Under the 32-degrees water is usually in form of ice and in temperatures over 212 it turns into steam. Usually a window has warmer air on the indoors -side than on the outside. The outside air is making the window slightly cooler than the air inside. Therefore the water vapor in air is cooled down when it makes contact with the glass. When it cools, it turns back to liquid water and that forms the droplets you can sometimes see on steamy window.

The same phenomenon you can see in metallic cold water pipes. Pipes, “sweat”, because they are so cold that water vapor in the air will condense into water.

Also, human exhaled air is warm and humid. Therefore on cold weather breath turns into steam. You can also try to breath towards window or a mirror – it should generate some steam on it.

The carrot is a root vegetable growing in ground. The part that is growing above earth is normally not used for food, but the underground root is delicious and healthy snack. Rich in  beta–carotene, which gives it an orange color. The carrot is after the potato one of the most popular root vegetables; it is eaten up to nine pounds per person per year.

Carrots are usually orange, but also white, purple, yellow and red carrots exists. In fairy tales and cartoons carrots are usually rabbits favorite food. Wild carrots do not exist everywhere, so in those areas rabbits need to eat some other plants.

Yoghurt is milk that is acidified using lactic acid bacteria. Yoghurt production is close to those of butter and sour cream. Also cheese is made by similar method.  Before the start of the 1900s yoghurt was consumed especially in South-East Europe, Central Asia, the Middle East and India. 

You can try the yogurt preparation at home for instance, together with the mother or father.

You will need a pot of milk and a half pots of seed of natural yoghurt. The milk is boiled in a saucepan and then allowed to cool to below 122 degrees. After cooling, the milk is mixed with yogurt – you can add milk powder, if you want a thicker yogurt. The mixture is then placed in the bowl or glass jars and placed in a warm place for 4-7 hours. A good trick is to heat the oven to 122 degrees, and then turn it off and put the jars there.

Ready yogurt can be flavored with sugar and banana for example. Self-made yogurt will remain in the refrigerator for about a week (on the surface may be formed whey)

This probably refers to a commercially available plastic bags. Shopping bag is usually used to carry the  groceries from shop to car and from car to home.

Plastic bags are made of plastic, and are most commonly used as carrier bags for groceries and as garbage bags. Plastic bags have all colors and sizes, and with different prints. They are thin, light and flexible. Extensive use of plastic bags spread in the mid-1970s. In 2002, the world was prepared in various sizes and qualities of plastic bags to a total of 4-5 trillion pieces

It is a good question why plastic bags are used. Plastic bags do not decompose and burning them causes toxic fumes. Thrown to the wild and in water Plastic bags cause problems for animals. Also biodegradable plastic bags do exist, but they are not as durable.

The same plastic bag can be used several times before it ends up as garbage bag.  Others prefer to use paper or fabric bags for carrying groceries. In some places, the use of plastic bags has imposed a special tax, or they are banned altogether.

In developing countries, little boys produce empty plastic bags, for example, soccer balls themselves.

Try to keep the hand closed, and then try to pick up toys from the floor, or eat yogurt with a spoon. Fingers distinguish humans and other primates from most other animals, because they allow objects sticking. You can also try to pick up objects with toes – it is possible, but not very easy. The fingers have made it possible to use different tools.

Tools are an important stage in human development. Weapons let people to be able to hunt for food for others than himself. Some people may have to stay at home, and some have gone hunting. Later, the tools have made it possible to cut down trees, to cultivate the land, build houses, etc.

The most important finger is the thumb. The thumb moves against other fingers allowing fine mechanical thumb-index finger grip. Compared with the technological superiority of man is to relate to the brain and this grip. It is very rare in the animal kingdom: possum, koala and some primates are able to slightly similar.

You can try out the necessity of the thumb, say put, a glove in your hand so that your thumb is not in its separate compartment. Try then pick up objects in your hand.

The idea of ​​self-moving trolley is old, even though from the discovery of the idea it took few hundred years, until the German Carl Benz produced the first car with internal combustion engine. As early as the 1400s there were designs for self-propelled vehicles, including Leonardo da Vinci to consider the use of a spring force in vehicles. Later, Isaac Newton developed the idea of ​​using steam eruption to power a car.

The earliest car is said to be  Nicolas Josef Cugnot’s three-wheel steam car dating back to 1769. This car was designed for military use to haul guns and other heavy objects.

Although the car was invented as early as the turn of the century, it took more than a hundred years, until the cars started to become common everywhere. Even in grandma’s and grandpa’s youth also horse was still in use as means of transport and to haul farming equipment. Gradually, cars and tractors, however, became more common and replaced the horse-drawn carriages and gadgetry.

Originally cars were made by hand and gasoline had to ne bought from pharmacy.  One of the automotive pioneers was the American Henry Ford, who built his first automobile factory based on conveyor belts. Once automotive color range was smaller than the current one. Ford is quoted as saying that customers can choose their car in any color as long as it is black.

Today, cars are produced in factories around the world. Most of the cars are still having combustion engines consuming petrol or diesel, but, for example, ethanol and electricity -powered cars are becoming more common. Cars are responsible for pollution which is making a mess in nature, and therefore cleaner cars are being developed all the time.

The earliest reference to shoes are some kind of findings from about ten thousand years ago. People are, since time immemorial times, learned that the soles of the feet are sometimes good to be protected against the cold, sharp stones or other harmful effects. On the other hand, where circumstances permit, also being bare footed has always been in fashion.

Prior to year 1000 numbers of different types of sandals were used, among other things, the Greeks, for whom the use of the shoes had been a wealth and status symbol. Roman sandals, in turn, developed into simple boots. Celts at 1100’s used leather shoes, which were heated by the fur inside of them.

In the Middle Ages shoes could be up to half a meter long with tapered tips. In the 1500’s came into fashion unwalkable, up to half a meter high platform soles, Chopin. In 1600’s it became more common to use shoe laces to tighten the shoes. The French Sun King Louis XIV used platform shoes and made courts wild around Europe.

Previously shoes were always handmade. Shoemakers guild was appreciated and they sewed shoes together from leather pieces. Today, cobblers, mainly fix shoes and copy keys. 1700’s the shoe industry developed and mass production began. The first shoe factories were founded, and as well the first shoe store opened in Boston. When 1900s’ approached , sports shoes were invented, among other things and manufacturing of shoes became easier thanks to the invention of the sewing machine. 

Today, most shoes are manufactured in factories in large Asian countries. Shoes might be made partly by hand, but now the factory can produces thousands of pairs of shoes a day, while the shoes entirely made by hand by the shoemaker could take a week.

As stated earlier in the stars and space articles, the space according to present knowledge emerged from the Big Bang with stars and planets and everything. The sun is the closest star to us – that’s why it looks so huge. Other stars are sometimes thousands of times larger than the sun, but they are so far away that they look like small dots in the night sky.

The stars will go out, and new ones are constantly born. Because the stars are so far away, their light’s trip here takes millions of years. Thus, how we see the starry sky is really like an old photo of what the stars looked like millions or billions of years ago. It may be that some of the stars we see are actually already gone and new ones have emerged to replace them.

How, then new stars  are born? The stars are created when the cold gas clouds are condensed together under their own weight. In the end, the resulting star settles to a stable state. At this stage the star receives energy from nuclear reactions, the fusion of hydrogen. Our sun is at this stage. Our Sun is about five billion years old and it is in the middle of its life cycle.

When all of the hydrogen starts being used, moves the star to fuse helium (the same substance that is in gas balloons) and the star’s core shrinks and heats up, but the outer parts expand and cool down. Thus the star becomes a red giant. After this, the stars with the mass of our sun become planetary nebula, with a central star being a dense white dwarf. By the time the fog will disappear, and cool white dwarf remains.

Heavy stars, about 10 times the mass of our Sun, are destined into a supernova explosion, which results in a gas cloud, in addition to either a neutron star or a black hole. Supernova is a huge explosion, where the fading star burst like a bomb and throws material all around the space. A black hole is a body, which traction force is so strong, that it will suck up everything – even light. It is believed that in the middle of our Galaxy is a huge black hole, whose name is Sagittarius A.