Book excerpt: Schweitzer offers this nontechnical, step-by-step guide to help computer users of all levels to better understand how the Internet works, and how to enjoy the benefits of the Internet while still maintaining computer security. Topics include secure Web browsing, cookie monitoring and removal, installing antivirus software, e-mail attachments and spam, securing a Web server, public key infrastructure, secure remote access and virtual private networks, and handling hacker attacks and cybercrime. The author is a vice president at an actuarial consulting firm, where he is responsible for corporate network design and security. Annotation copyrighted by Book News Inc., Portland, OR.