Every single day, millions of glass bottles are produced in factories located across the world. The raw glass is heated to exactly 1700 degrees Fahrenheit in specialized furnaces, and then it is shaped into bottles by precision machines. All finished bottles are inspected automatically by electronic sensors for cracks, chips, and other defects before shipping. Over 200 million tons of glass containers are recycled annually in countries with strong environmental programs. This recycling process was first developed in the early 1900s, but it has been significantly improved with modern technology.