The primary material used in the construction of glass is silica, commonly found in sand. Silica is a compound made of silicon and oxygen, and when heated to high temperatures, it melts and can be shaped into various forms. Other ingredients, such as sodium carbonate (soda) and calcium oxide (lime), are often added to enhance the properties of the glass, including its durability and clarity. The process of glass-making has evolved over centuries, resulting in a range of glass types used for different applications, from windows to intricate art pieces.