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Classical hypertext navigation occurs among "static" documents, and, for web users, this experience is reproduced using static web pages. However, web navigation can also provide an interactive experience that is termed "dynamic". Content (text, images, form fields, etc.) on a web page can change, in response to different contexts or conditions. There are two ways to create this kind of interactivity:
The result of either technique is described as a dynamic web page, and both may be used simultaneously.
To adhere to the first definition, web pages must use presentation technology called, in a broader sense, rich interfaced pages. Client-side scripting languages like JavaScript or ActionScript, used for Dynamic HTML (DHTML) and Flash technologies, are frequently used to orchestrate media types (sound, animations, changing text, etc.) of the presentation. The scripting also allows use of remote scripting, a technique by which the DHTML page requests additional information from a server, using a hidden Frame, XMLHttpRequests, or a Web service.
Web pages that adhere to the second definition are often created with the help of server-side languages such as PHP, Perl, ASP or ASP.NET, JSP, and other languages. These server-side languages typically use the Common Gateway Interface (CGI) to produce dynamic web pages. These kinds of pages can also use, on client-side, the first kind (DHTML, etc.).
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The Client-side dynamic content is generated on the client\'s computer. The web server retrieves the page and sends it as is. The web browser then processes the code embedded in the page (normally JavaScript) and displays the page to the user.
The innerHTML property (or write command) can illustrate the "Client-side dynamic page" generation: 2 distinct pages, A and B, can be regenerated (by an "event response dynamic") as document.innerHTML = A and document.innerHTML = B; or "on load dynamic" by document.write(A) and document.write(B).
The problems with client-side dynamic pages are:
Server-side dynamic content is a little bit more complicated.
Server-side has many possibilities for dynamic content, but the use of it can be a strain on low-end, high-traffic machines. Some web sites use the Robots Exclusion Standard to keep web crawlers from accessing dynamic pages for this reason. If not properly secured, server-side scripts could be exploited to gain access to a machine[citation needed].
Ajax is a newer web development technique for interchange dynamically contents with the server-side, without reload the webpage. Google Maps is an example of a web application that uses Ajax techniques.
It is difficult to be precise about "dynamic web page beginnings" or chronology, because the precise concept makes sense only after the "widespread development of web pages". Context and dates of the "web beginnings":
For server-side dynamic pages:
For client-side:
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