The highway code contains rules concerning the safety equipment of bicycles.
During its orbit around the Earth, the visibility of the Moon's illuminated part constantly changes.
Ancient Roman conquerors had effective siege engines developed for attacking fortifications.
Hero of Alexandria is the inventor of the first steam engine, although he regarded it as an entertaining toy.
The first dwellings in human history provide a lot of information about the lifestyle of our ancestors.
Jupiter is the largest planet of the Solar System, it has two and a half times the mass of all the other planets combined.
Possible traces of water and life are sought on Mars.
The main protagonists of World War II were tanks.
The concentration camp established on Polish territory was the administrative centre of a huge camp complex.
The palace of Charlemagne was not only the centre of his empire, but also a centre of culture.
Mercury is innermost and smallest planet of the Solar System.
Neptune is the outermost planet of the Solar System, the smallest of the giant planets
Saturn is the second largest planet in the Solar System, easily recognisable by its rings.
Uranus is the 7th planet from the Sun, a gas giant.
The battle of the Greek-Persian War became famous for the heroic sacrifice of the Spartan soldiers.
The first indoor theatre in modern history to be constructed according to the theatre-building codes of Antiquity was inaugurated in 1585.
Submarines had an important role in naval warfare as early as World War I.
The suspension bridge that stretches above the strait between San Francisco Bay and the Pacific Ocean was opened in 1937.
In alkaline batteries electric current is generated by electrochemical reactions
DC motors consist of a permanent magnet and a coil within the magnet, with electric current flowing in it.