Leo Baekeland invented Bakelite, the world's first fully synthetic plastic, made from phenol and formaldehyde. Unlike previous plastics derived from plants, Bakelite was a 'thermosetting' plastic; once molded, it would not melt or change shape even under high heat or pressure. It was also an excellent electrical insulator. These properties made it the 'material of a thousand uses.' It was used to manufacture everything from early telephone housings and radios to billiard balls and jewelry. Bakelite inaugurated the 'Age of Plastics,' demonstrating that humans could create entirely new materials with specific properties that did not exist in nature. While it led to massive industrial progress, it also marked the beginning of the modern challenge of plastic waste, as synthetic polymers do not biodegrade easily.