Hall & Oates are the best-selling musical duo of all-time with a staggering number of monster hits, but the rock establishment has never taken them quite as seriously as the huge fan base. "It's probably because they had their own opinions about what constituted exceptional music in that period of time," says Hall. "And it was based on a lot of things that I wasn't really interested in. I have slightly different roots than most of the [rock] writers." Their induction into the Hall of Fame clearly shows that times have changed. Here's a look back at their incredible 40-year career.