Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects. The animal on the cover of Web Security, Privacy & Commerce, Second Edition is a whale shark. Sharks have lived on the Earth for over 300 million years, and populate all the oceans of the world (as well as some freshwater lakes and rivers). They are related to skates and rays, differing from ordinary bony fish in having a cartilaginous skeleton that makes their bodies unusually flexible. Unlike bony fish, sharks give birth to live young, in small litters.

A common misconception about sharks is that they need to keep swimming at all times. While they do need to move their fins constantly in order to stay afloat, many species of sharks like to rest on the bottom of the ocean floor.

Sharks make excellent predators because of their well-developed sensory system (not to mention their big, sharp teeth). They have excellent eyesight and an unusually keen sense of smell; they are known to be able to locate prey from a single drop of blood.Sharks can also sense electrical currents in the water indicating the presence of other fish. They retain several rows of teeth, which roll outward to replace those that are lost.

The whale shark, on the other hand, is a kinder, gentler shark. Whale sharks (Rhinocodon typus) have a large flat head, a wide mouth, and tiny teeth. As a filter feeder, they feed primarily on plankton and small fish. They have distinctive spotted markings on their fins and dorsal sides. Whale sharks are so named because of their size: they may weigh more than 18 metric tons and measure up to 60 feet long. They are the largest species of fish alive today.

Whale sharks live in tropical and temperate seas. They pose little or no risk to humans. In fact, whale sharks are considered a particular treat to divers, since they are impressive in size but are slow-moving and not aggressive. Colleen Gorman was the production editor and the copyeditor for Web Security, Privacy & Commerce, Second Edition. Melanie Wang and Sue Willing were the proofreaders. Matt Hutchinson provided quality control. Mary Brady, Phil Dangler, Maureen Dempsey, Derek Di Matteo, Catherine Morris, and Edie Shapiro provided production support. John Bickelhaupt wrote the index.

Edie Freedman designed the cover of this book. The cover image is a 19th-century engraving from the Dover Pictorial Archive. Emma Colby produced the cover layout with QuarkXPress 4.1 using Adobe's ITC Garamond font.

David Futato designed the interior layout. Neil Walls updated the files to FrameMaker 5.5.6 using tools created by Mike Sierra. The text font is Linotype Birka; the heading font is Adobe Myriad Condensed; and the code font is Lucas-Font's TheSans Mono Condensed. The illustrations that appear in the book were produced by Robert Romano and Jessamyn Read using Macromedia FreeHand 9 and Adobe Photoshop 6. The tip and warning icons were drawn by Christopher Bing. This colophon was written by Linda Mui.

Whenever possible, our books use a durable and flexible lay-flat binding. If the page count exceeds this binding's limit, perfect binding is used.