Dan Gookin has been writing about technology for over 20 years. Perhaps his most famous title is the original DOS For Dummies, published in 1991. It became the world's fastest-selling computer book. From that book spawned the entire line of For Dummies books, which remains a publishing phenomena to this day. Dan's most recent titles include Word 2007 for Dummies, Laptops for Dummies, 2nd Edition,  and PCs For Dummies, 10th Edition. He also maintains the vast and helpful Web page, www.wambooli.com.