2004年10月19日，美国互联网巨头雅虎与金山、当当、天极等12家中国知名公司建立了合作伙伴关系，为它们提供国内最大容量的1G电子邮箱和其他服务。这一举动似乎违反了雅虎原先作出的不涉足门户网站市场的承诺，而且和中国本土巨头新浪、搜狐和网易展开了明刀明枪的竞争。中国日报网站消息：Yahoo! China said yesterday that it had formed an e-mail alliance with Chinese firms like NASDAQ-listed travel service company Ctrip, game websites including Haofang, e-commerce firm Dangdang, IT information portals Chinabyte, Enet and Donews, and software company Kingsoft. The Chinese branch of the US Internet giant will first provide its free e-mail technology to the 12 companies and their users can register such accounts with a capacity of as much as one gigabyte. Yahoo! China spokesman Tu Jianlu said that more than 50 per cent of China's 80 million Internet users use the services of the 12 companies. These users are highly educated in terms of the Internet and are loyal, making them very valuable to his company.Portal的本意是“大门，入口，进入手段”，在IT界主要表示“门户网站，网络准入”。业界对portal的定义有很多种分类，比如把portal定义为企业信息门户、协作门户、专业门户、知识门户等等。相关的术语有：Enterprise Information Portal （企业信息门户）；virtual portal（虚拟门户）；vertical portal（针对特定主题的门户网站）等.