Microsoft Office Tutorials and References
In Depth Information
Security Threats on Your Computer
Antivirus software , sometimes referred to as virus-protection software , searches
executable ﬁ les for the sequences of characters that might cause harm and disinfects the ﬁ les
by erasing or disabling those commands. Figure 24 shows the dialog box that appears
when the Trend Micro antivirus program is scanning a computer for potential threats. The
computer advertised in the Visual Overview comes with a 30-day trial version of
Antivirus scan in progress
about the scan
lists nu mber of possible
security threats found so far
Some software programs contain other programs called spyware that track a
computer user’s Internet usage and send this data back to the company or person who
created it. Most often, this is done without the computer user’s permission or knowledge.
Anti-spyware software can detect these programs and delete them. Adware is software
installed with another program, usually with the user’s permission, that generates
advertising revenue for the program’s creator by displaying targeted ads to the program’s user.
A ﬁ rewall is like a locked door on your computer. It prevents other computers on the
Internet from accessing your computer and prevents programs on it from accessing the
Internet without your permission. A ﬁ rewall can be either hardware or software. A
hardware ﬁ rewall provides strong protection against incoming threats. A router usually has a
built-in ﬁ rewall. Software ﬁ rewalls track all incoming and outgoing trafﬁ c. If a program
that never accessed the Internet before attempts to do so, or if another computer attempts
to connect to your computer, the user is notiﬁ ed and can choose to forbid access. Several
free software ﬁ rewall packages are available.
Criminals are getting more aggressive as they try to ﬁ gure out new ways to access
computer users’ personal information and passwords. One way they are doing this is
with spoofed Web sites. A spoofed site is a Web site set up to look exactly like another
Web site, such as a bank’s Web site, but which does not actually belong to the
organization portrayed in the site. The site developer creates a URL (Uniform Resource Locator;
an address on the Web) that looks similar to a URL from the legitimate site. Usually,
spoofed sites attempt to convince customers of the real site to enter personal
information, such as credit card numbers, Social Security numbers, and passwords, so that the
thief collecting the information can use it to steal the customer’s money or identity.
Figure 25 shows the Internet Explorer browser when a known spoofed site is visited.