(FORTUNE Magazine) – Even if we weren't all half-convinced that the world's computers will lock up on Jan. 1, we would have to regard the coming turn of the calendar with a certain awe. It's the close of a boom year at the end of a booming decade at the finale of a soaring century--a kind of triple witching hour of business history. For now, but not much longer, we live in the same remarkable unit of time that enfolds both Henry Ford and Bill Gates, the Auto Age and the Information Era, the invention of the transistor and the creation of 150 serving suggestions for Spam. In this special report, FORTUNE focuses a wide-angle lens on the phenomenal 100 years just past. Take a look. Because once the 21st century begins, you'll be far too busy to look back again.