"Most people lock their doors and windows, use a paper shredder
to protect themselves from identity theft, and install antivirus
software on their computers. Yet they routinely surf the Internet
without giving a second thought to whether their browser is secure
and their personal information safe. Unfortunately, it's easy for
someone with nefarious intentions to use a Web site to glean data
from--or introduce spyware to -- your computer. Even worse,
sometimes all you have to do is randomly click on a site to have
your data probed in a most unwelcome way.
"Mozilla Firefox has several security settings you can adjust
via the Preferences pane, but there are also more than 150 privacy
and security extensions you can add as well..."