Anti-virus software protects a computer from viruses, Trojan horses, worms and other forms of malicious software (malware). Antivirus software protects a computer by searching its hard disk for programs and comparing the findings against a known set of malicious software; and, if suspicious files are found, deleting or quarantining the viruses. Antivirus software is necessary for both Windows and Mac users. Two leading Internet security companies, Intego and Symantec, both sell duel protection antivirus programs, which protects Mac OS X and Windows from all known viruses.
- Tails (operating system) (Linux-based) and Tor (anonymity network) Firefox browser encryption for Internet anonymity to protect unalienable rights