Pollution is the detrimental effect of human activity on the natural environment.
The ear converts the vibrations of air into electric signals which are then processed by the brain.
This animation demonstrates how the Earth and the Moon were formed.
The desalination process produces drinking water from seawater.
The most famous and most magnificent amphitheater of Rome was built in the 1st century.
This animation demonstrates different types of volcanic eruptions.
The round tower of the largest fort in the Arabian Peninsula had an ingenious defense system.
This animation presents the formulas to calculate the perimeter and area of shapes as well as the surface area and volume of solids.
This animation introduces the most important organ systems of the human body.
This animation demonstrates the type of engine most commonly used in cars.
The church of the "Holy Wisdom," built in the Byzantine Empire, had been one of the largest religious buildings until 1935, when it was converted into a museum.
Large carnivores, perhaps the best known of dinosaurs.
The world's most famous citadel, the Acropolis of Athens was built in the 5th century B.C., during the Age of Pericles.
This animation presents some interesting facts in physical geography.
Visit the workshop of the Renaissance polymath and his most influential inventions and works of art.
Reindeer are the northernmost deer species.
The main sources of water pollution are industry, agriculture and urban areas.
The pancreas and the liver empty digestive juices into the duodenum.
The difference between the temperature of the polar and equatorial zones causes atmospheric circulation which is affected by a number of factors, including...
The International Space Station is a habitable satellite built with the cooperation of 16 countries.