Google and Microsoft are competing for DoubleClick, an online advertising company

Google, Yahoo! And Microsoft, the three leading search engine makers, are competing to be the top companies that want to advertise on the Internet

A one-stop shop. To achieve this, web companies need not only the ability of their own networks to attract large amounts of traffic and provide highly relevant search ads, but they also need to sell ads on other popular sites and capture more information about their users.