Internet

The Internet is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a network of networks that consists of private, public, academic, business and government networks, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries a vast range of information resources and services, such as applications of the World Wide Web, e-mail and file sharing.

Internet is a proper noun, as there is only one, and is spelt with a capital I.