A mechanism for providing contextual information for a web page. In the preferred embodiment, a browser displays multiple web pages in multiple windows in a parent-child hierarchy on a display screen. The browser maintains this hierarchical relationship by building and updating a window-list data structure,...http://www.google.com.hk/patents/US6177936?utm_source=gb-gplus-share專利 US6177936 - Browser hierarchical contextual information for web pages
