Glass is primarily made from silica, which is silicon dioxide (SiO2). Other ingredients, such as soda (sodium carbonate) and lime (calcium oxide), are often added to lower the melting point of silica and enhance the durability of the final product. The combination is heated in a furnace until it melts into a molten form, which can then be shaped into various items, from windows to bottles. Additional materials can be incorporated to produce different types of glass with specific properties, such as colored glass or tempered glass. The versatility of glass makes it a widely used material in numerous industries.