As Yahoo! struggled to lift itself out of the dotcom slump a few years ago, it faced a big decision. Google was dazzling the world of Internet search engines with its building of a massive index of Web documents. And a California-based company called Overture Services was beginning to convince the world that search-engine advertising could be wildly lucrative.

Yahoo! had neither its own search engine, nor a way to fully reap the profits from Internet searching. Yahoo! executives needed to decide whether to get into the massively expensive search-engine game – and how.

So after Overture sent over a proposal about a partnership in mid-2001, the Yahoo! top brass swang into action.

"When people started looking at the numbers, there was almost disbelief," recalled Jeff Weiner, Yahoo!'s senior vice president of search and marketplace. "It's like 'What?! Search is capable of generating this much value?' "

Today, Internet searching has become a cornerstone of Yahoo!'s resurgence from the dotcom slump.

The company doesn't break out numbers. But analysts estimate Yahoo!'s search-engine advertising revenue of $1.2 billion last year accounted for 58 per cent of all ad revenue and 45 per cent of the company's total net revenue.

Today, while Google's name is still synonymous with Internet search, many consider Yahoo!'s search technology to be at least as good as anybody's. US Internet users went to Yahoo! for 31 per cent of their search queries in February, according to comScore Networks. Google captured 36 per cent.