Drums are played by hitting the membrane. There are many versions of drums.
A floatplane (sometimes called hydroplane) is an aircraft capable of taking off not only dry land, but water too.
A transitional form between fish and tetrapods, or four-limbed vertebrates.
German sordiers in the First World War were well trained and used modern weapons.
A colourless, odourless, non-reactive gas, it constitutes 78.1% of Earth´s atmosphere.
Several European countries joined the conquest of the New World, making America a colourful continent.
The Canadian helicopter is one of the most widely used helicopters in the world.
Soldiers of the ancient Macedonian Kingdom were dreaded warriors.
The Gaul city Alesia, which was defended by Vercingetorix, was besieged by the Roman forces of Julius Caesar in 52 BC.
Based on their life cycle, insects can be grouped into three categories: ametabolous, hemimetabolous or holometabolous insects.
The first Hungarian-made locomotive powered directly from the national electricity network without complicated transformations.
The protective embankment, or, in case of minor floods, the summer dyke ensures the protection against flood damage.
Market towns became the most common type of towns in the Kingdom of Hungary by the Late Middle Ages.
The castle of Eger got its final shape and became an important component in the new chain of border forts in the 16th century.
The prosperity of the eastern part of the Roman Empire started in the early 4th century, during the reign of Emperor Constantine.
The brain and skull underwent significant changes during human evolution.
A prehistoric amphibian and an early representative of the Tetrapods, which became extinct 360 million years ago.
Pollen serves to fertilise the egg of plants. Pollen grains come in a variety of shapes and sizes, characteristic of the species.
This animation demonstrates how sonar works.
This animation demonstrates how lifts work.