Blood vessels in fishes' gills absorb oxygen and release carbon dioxide.
Tall buildings are mementoes of human history and technological development.
Viruses consist of protein and DNA or RNA; they reprogram infected cells to produce more viruses.
Villages were the first permanent human settlements
A Zeppelin is a type of controllable, rigid airship.
The theorem formulated by Leonhard Euler describes one of the basic properties of convex polyhedra.
The most popular European-made transport aircraft before World War II.
In 1946 a Hungarian scientist was the first person to detect radar echoes from the Moon.
Drums are played by hitting the membrane. There are many versions of drums.
A Romanesque style Benedictine church with a special gateway, built in the 13th century in Hungary.
The iron lattice tower, erected for the 1889 World Fair, became the symbol of the capital city of France.
A legendary fighter plane used by the German air force in World War II.
The efficient reconnaissance aircraft has been used by the CIA since the Cold War.
The best-known piece of the Hungarian Crown Jewels is the Holy Crown.
Tanks developed in the mid-1910s quickly became the most important weapons of land-based military operations.
Soldiers of the Wehrmacht in World War II were well-trained and well-equipped with modern weapons.
The castle of Belgrade (Nándorfehérvár) was one of the most important components in the chain of Hungarian border forts.
This animation demonstrates the states and largest cities of the USA.
An exercise about the generation of solids of revolution.
This animation demonstrates various types of cones and pyramids.