Terry Semel

May 2001-June 2007: Yahoo made a sharp departure from Koogle when it looked to Hollywood for Terry Semel, who had spent 24 years at Warner Bros. A technology company run by a Hollywood suit?

At first, it worked. Semel was given credit for cutting corporate initiatives that made little sense and rationalizing business groups. He also diversified Yahoo's business away from strict dependence on display ads with alternative revenue streams such as premium services and classified listings. Semel saw Yahoo as a media play and pushed as hard as he could to realize that vision.

But the company lurched from one financial disappointment to the next. Semel was unable to come up with a way for this very first-generation Web company to stave off younger rivals. In particular, he was painfully slow to build a successful search advertising business and got left behind by Google.

One side note: Semel tried and failed to entice a fresh-faced Harvard dropout named Mark Zuckerberg to sell Yahoo something called Facebook. Had Zuck said yes, the tech landscape would look a lot different today.