Yahoo!
Yahoo grew rapidly throughout the 1990s. Yahoo went public in April 1996 and its stock price rose by 600 percent within two years. Like many search engines and web directories, Yahoo added a web portal, putting it in competition with services like Excite, Lycos and America Online. By 1998, Yahoo was the most popular starting point for web users, and the human-edited Yahoo Directory the most popular search engine, receiving 95 million page views per day which was triple the number compared to rival Excite. It also made many high-profile acquisitions. Yahoo began offering free e-mail from October 1997 after the acquisition of RocketMail, which was then renamed to Yahoo! Mail. In 1998, Yahoo! decided to replace AltaVista as the crawler-based search engine underlying the Directory with Inktomi. Yahoo's two biggest acquisitions were made in 1999 - that of Geocities for $3.6 billion, and Broadcast.com for $5.7 billion.
Yahoo! Publisher Network
The Yahoo! Publisher Network (abbreviated YPN) was an advertising network launched on August 2, 2005 by Yahoo! and effectively closed on April 30, 2010. The service only accepted US-Based publishers. YPN provided cost per click contextual advertising as well as various tools and services to assist publishers in building and improving their websites.