During its orbit around the Earth, the visibility of the Moon's illuminated part constantly changes.
Neptune is the outermost planet of the Solar System, the smallest of the giant planets
The palace of Charlemagne was not only the centre of his empire, but also a centre of culture.
The invention of the ballpoint pen made writing a lot easier.
Vertical forces can break up layers of rock into fault blocks, which then move vertically along the fracture planes.
The concentration camp established on Polish territory was the administrative centre of a huge camp complex.
The highway code contains rules concerning the safety equipment of bicycles.
The changing bicycle, at first mocked as a toy, is a true mirror of the technical development over the last three centuries.
Xe tăng là vũ khí chính trong Chiến tranh thế giới thứ hai.
Những nơi ở đầu tiên trong lịch sử loài người cung cấp rất nhiều thông tin về lối sống của tổ tiên chúng ta.
Hero of Alexandria is the inventor of the first steam engine, although he regarded it as an entertaining toy.
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.
A mobile, nuclear-capable ballistic missile developed at the end of the Cold War.
Large construction sites provide archaeologists searching for artefacts with a great deal of work.
The Apache attack helicopter, named after an American Indian tribe, was developed for the United States Army.
The work of smiths – one of the first professions in history – became even more important in the Middle Ages.
A wide variety of torture devices were in use in medieval dungeons.
Chiến tranh tĩnh là một trong những đặc điểm của Chiến tranh thế giới thứ nhất.
The German liquid-propellant rocket, developed during WWII, was the first known man-made object to reach space.
'Pháo đài bay' được Boeing phát triển để phục vụ cho Lực lượng Không quân Hoa Kỳ.