Use A Firewall
A firewall is a software program or piece of hardware that prevents unauthorized Internet traffic from entering or leaving your computer. A firewall helps make you invisible on the Internet and blocks all communications from unauthorized sources. The best way to ensure protection is to use both a firewall and anti-virus software.
Some operating systems have built-in firewalls. The video tutorials below show you how to activate the firewalls built into Windows and Macintosh OS X.
Enable the built-in firewall in Windows XP
This video tutorial shows you how to enable the firewall option built into the Microsoft XP operating system. This option is available only if you have this operating system version.
Start the built-in firewall in Mac OS X (version 10.2 or above)
This video tutorial shows you how to start the built-in firewall of the Macintosh OS X operating system. This option is available only to users of the Macintosh OS X operating system version 10.2 or later.
More Information on these Categories
Detects and removes computer viruses.
Hardware or software that secures computer files by blocking unauthorized access.