After two years of on-and-off talks and speculation, Microsoft offers to buy Yahoo for $31 per share, or $44.6 billion.
CLASHING TITANS: Microsoft wants to challenge Google's dominance in the search-advertising industry. In recent years, Microsoft launched its own Web advertising platform and overhauled its search engine, but neither move helped close the gap with Google. Yahoo would bring in some much-needed search traffic and bulk up its display advertising business.
THE FRAY: Analysts say others might jump into the ring with competing bids for Yahoo - including News Corp., IAC/InterActiveCorp. or Google itself.
MARKET WATCH: Microsoft posted blockbuster earnings last week, while Yahoo forecast "strong headwinds." Investors sent Yahoo's stock up 45 percent Friday on the news; Microsoft's stock sank 7 percent.
WHAT'S NEXT: Yahoo's board says it will study the offer; then, it's up to shareholders and regulators to approve.