Silicon
- Latin name: Silicium
- German name: Silizium
- Symbol: Si
- Atomic number: 14
- Period (row): 3
- Group (column): 14
- Element group: metalloid
- Atomic mass: 28.0855
- Discovered in: 1823
Most free silicon is used in the steel refining, aluminium-casting, and fine chemical industries (often to make fumed silica). Even more visibly, the relatively small portion of very highly purified silicon used in semiconductor electronics (< 10%) is essential to integrated circuits — most computers, cell phones, and modern technology depend on it. Silicon is the basis of the widely used synthetic polymers called silicones.