Visualization of the various routes through a portion of the Internet
In the general sense, an internet (with a lowercase "i", a shortened form of the original inter-network) is a computer network that connects several networks. As a proper noun, the Internet is the publicly available internationally interconnected system of computers (plus the information and services they provide to their users) that uses the TCP/IP suite of packet switching communications protocols. Thus, the largest internet is called simply "the" Internet. The art of connecting networks in this way is called internetworking.

A computer network is a system for communication among two or more computers.
Computer networks may be categorized with respect to range:
personal area network (PAN)
wireless PAN
local area network (LAN)
wireless LAN
metropolitan area network (MAN)
wide area network (WAN)
(Tiny area network (TAN)

Adware or advertising-supported software is any software package which automatically plays, displays, or downloads advertising material to a computer after the software is installed on it or while the application is being used.
Malicious websites may attempt to install spyware on readers' computers. In this screenshot a spamblog has triggered a pop-up that offers spyware in the guise of a security upgrade.