There are many government agencies both in the U.S. and around the world who restrict their employees from visiting social networking sites (SNS) through the use of afirewall filter.
And since broadband connections are considered a tasty target for some criminal hackers who might try to use your line for malicious purposes, it includes afirewall, which can defend your machine from prying eyes.
He said people should sign up for automatic updates, make sure the applications they use are regularly patched, use anti-virus software and run afirewall.