Cyber-attacks have become a big deal in the mainstream news recently. Several major Web sites fell victim to denial of service attacks in July and August (read more about denial of service attacks in "Zombie Attack"). Twitter was the most notable to get victimized, as hackers twice brought the social networking site to its knees for several days. Media reports suggested Russian operatives staged at least one of the attacks to silence a blogger critical of Russia's policies toward the nation of Georgia.
However, cyber-attacks threaten not only businesses, but also critical infrastructure. With more and more of American society reliant on the Internet, terrorists could theoretically bring down important parts of the nation's infrastructure--hospitals, utilities, communication channels such as Twitter or government agencies, for example--through Web-based attacks.