The Internet is a globally interconnected system of computer networks. The World Wide Web (WWW) is the interconnected system of documents and pages.
Connections between machines can be two-way. Digital subscriber lines (DSL), which make use of complicated DSP circuits, allow data to be transmitted on the same cables as phone lines.
The Internet protocol suite (TCP/IP) is a set of communication protocols used in computer networking and the Internet. They allow consistent ways for each machine to communicate with each other.