Norton Internet Security, developed by Symantec Corporation, is a computer program that provides malware prevention and removal during a subscription period and uses signatures and heuristics to identify viruses. Other features included in the product are a personal firewall, email spam filtering, and phishing protection. With the release of the 2015 line in summer 2014, Symantec officially retired Norton Internet Security after fourteen years as the chief Norton product. It is superseded by Norton Security, a rechristened adaptation of the Norton 360 security suite.
Symantec distributed the product as a download, a boxed Compact Disc (CD) copy, and as OEM software. Some retailers also distributed it on a USB flash drive. Norton Internet Security held a 61% market share in the United States retail security suite category in the first half of 2007. In this study, competitors, in terms of market share, included security suites from CA, Inc., Trend Micro, and Kaspersky Lab.