The Internet is considered the world's largest network because it connects millions of private, public, academic, business, and government networks, linking billions of devices globally. It enables vast amounts of information to be shared and accessed, providing a platform for communication, commerce, education, and entertainment universally. The scale and reach of the Internet far exceed that of any local or private networks, such as Local Area Networks (LAN) which are confined to a limited area, or Intranets and Extranets, which cater to specific organizations or groups. The defining characteristic of the Internet is its open, decentralized nature, allowing for an extensive interconnection of networks across the globe.