What are the four great inventions in English?

The invention period was in the Han Dynasty, and the improvement period was in the Han Dynasty.

2, compass compass

It's called Sina, and its main component is a magnetic needle installed on the shaft. Under the action of natural geomagnetic field, the magnetic needle can rotate freely and keep in the tangent direction of magnetic meridian, and the south pole of the magnetic needle points to the geographical south pole (magnetic north pole), so we can use this property to judge the direction.

2. gunpowder

Gunpowder is one of the four great inventions in China. It is a substance that can burn quickly and regularly under the action of appropriate external energy, and at the same time produce a large number of high-temperature gases. Militarily, it is mainly used as the propellant of bullets and shells, the propellant of rockets and missiles and the energy source of other driving devices, which is an important part of ammunition.

4. Printing and printing

Printing is one of the four great inventions of working people in ancient China. Engraving printing was invented in the Tang Dynasty and was widely used in the middle and late Tang Dynasty. Song Renzong and Bi Sheng invented movable type printing, which marked the birth of movable type printing.

The historical significance of the four great inventions:

The four great inventions are a series of glorious footprints left by China's ancient ancestors to the world, and they are symbols of great contributions made by human civilization and progress.

(1) the invention of papermaking: it provided economical and convenient writing materials for human beings and set off a revolution of human writing carrier;

The invention of block printing greatly promoted the spread of culture;

(3) The invention of the compass provided conditions for the navigation activities of European navigators;

(4) Invention of gunpowder weapons: The use of gunpowder weapons changed the way of fighting, helped the European bourgeoisie destroy feudal fortresses and accelerated the historical process in Europe.