Silicium, commonly known as silicon, is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster. Silicium is the second most abundant element in the Earth's crust, primarily found in the form of silicates and silica. Silicium plays a crucial role in modern technology, especially in the production of semiconductors used in electronic devices. Its unique properties allow it to conduct electricity under certain conditions, making it essential for the manufacturing of computer chips and solar cells.