Example of Anchor Tag in HTML Other Markup Languages iNput Extensible Markup Language(XML) The text is published by <aHref=httP://www.prenhall.com> Tag names can be created as needed Prentice Hall, </A> one of the Example for a corporate phone book: larger publishers of Computer Science textbooks Produces The text is published by Prentice Hall, one of ace koem 32 C/OrSon the larger publishers of Computer Science 物765555-1234/ Caching in Browsers Types of Web Pages Cache for recently accessed a stati HTML pages Stored in file Item normally fetched from cache Dynamic Formed by server Http can verify timestamp before Created on demand fetching new copy Output from a program Use Common Gateway Interface(CGr) Types of Web Pages(cont) Summary of Web Document Types Active Web documents can be grouped into Executed at client depending on when the information in Consists of a computer program Can interact with user uthor revises the dour Use Java technology whenever a ation displayed by an active document e after the document has been loaded into a browser6 哈工大计算机学院 李全龙 Network Application Development Server Software Design 31 Example of Anchor Tag in HTML „ Input The text is published by <A HREF=http://www.prenhall.com> Prentice Hall, </A> one of the larger publishers of Computer Science textbooks. „ Produces The text is published by Prentice Hall, one of the larger publishers of Computer Science textbooks. 哈工大计算机学院 李全龙 Network Application Development Server Software Design 32 Other Markup Languages „ Extensible Markup Language (XML) does not specify layout „ Tag names can be created as needed „ Example for a corporate phone book: 哈工大计算机学院 李全龙 Network Application Development Server Software Design 33 Caching in Browsers „ Cache for recently accessed „ HTML pages „ Images „ Item normally fetched from cache „ User can override „ HTTP can verify timestamp before fetching new copy 哈工大计算机学院 李全龙 Network Application Development Server Software Design 34 Types of Web Pages „ Static „ Stored in file „ Unchanging „ Dynamic „ Formed by server „ Created on demand „Output from a program „ Use Common Gateway Interface (CGI) technology 哈工大计算机学院 李全龙 Network Application Development Server Software Design 35 Types of Web Pages (cont) „ Active „ Executed at client „ Consists of a computer program „ Can interact with user „ Use Java technology 哈工大计算机学院 李全龙 Network Application Development Server Software Design 36 Summary of Web Document Types Web documents can be grouped into three categories depending on when the information in the document changes. The information in a static document remains unchanged until the author revises the document. The information in a dynamic document can change whenever a server receives a request for the document. Information displayed by an active document can change after the document has been loaded into a browser