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. Butterflies are featured on the cover of Oracle Distributed Systems. These are three of the thousands of species of butterfly. Butterflies, along with moths and skippers, make up the order Lepidoptera. The word "Lepidoptera" is derived from the Greek words lepic, meaning "scale," and pteron, meaning "wing." And, in fact, butterfly and moth wings are covered entirely in tiny, overlapping scales. The coloration of these fragile scales is what creates the spectacular, shimmering colors of the butterfly. The wing membrane itself is transparent and without color. Butterfly scales and hairs are covered in a thin layer of wax, making these insects water-repellent. Most butterflies fly by fluttering their wings at a relatively slow rate, sometimes as slowly as 10 beats per second, approximately four miles per hour. Unlike many other insects, who beat their wings so fast that they become just a blur in flight, the butterfly's wings are clearly visible during its fluttering flight. Butterflies are as well known for their four-stage metamorphosis as they are for their colorful wings and graceful fluttering. An adult female butterfly lays a large number of eggs, usually on or near food plants. The larva, better known as the caterpillar, develops within the egg and eats its way out. It then continues to eat almost constantly for a period ranging from one month to two years, depending on the butterfly species, periodically molting its skin during the process. The caterpillar then produces a pupa, or chrysalis, a mummylike structure. When the adult butterfly is fully formed, it breaks out of the pupa, its body and wings harden, and it takes off in search of food. Melanie Wang was the production editor, and Norma Emory was the copy editor for Oracle Distributed Systems. Sheryl Avruch was the production manager, and Jane Ellin and Ellie Maden provided quality control reviews. Betty Hugh and Sebastian Banker provided production support. Chris Reilley created the illustrations using Adobe Photoshop 5 and Macromedia FreeHand 8. Mike Sierra provided FrameMaker technical support. Ruth Rautenberg wrote the index. Edie Freedman designed the cover of this book, using a 19th-century engraving from the Dover Pictorial Archive. The cover layout was produced by Kathleen Wilson with QuarkXPress 3.32 using the ITC Garamond font. Kathleen Wilson designed the diskette label. The inside layout was designed by Nancy Priest and Alicia Cech and implemented in FrameMaker 5.5 by Mike Sierra. The text and heading fonts are ITC Garamond Light and Garamond Book. This colophon was written by Clairemarie Fisher O'Leary. Whenever possible, our books use a durable and flexible lay-flat binding, either RepKover or Otabind. If the page count exceeds the mamximum bulk possible for this type of binding, perfect binding is used.