A dynamic website is one that changes or customizes frequently and automatically. Dynamic server-side pages are generated “on the fly” computer code that produces HTML code (CSS are responsible for the appearance and therefore are static files). There is a wide range of software systems, such as CGI, Java servers and Java Server Pages (JSP), Active Server Pages, and ColdFusion (CFML) that are available to generate dynamic Web systems and dynamic sites. Various frameworks for web applications and web template systems are available for general programming languages ​​for purposes such as Perl, PHP, Python and Ruby to make it faster and easier to create complex dynamic websites.

A site can display the current state of a dialogue among users, monitor a change situation, or provide information in a certain customized way to the individual user’s needs. For example, when you are prompted for the first page of a news site, code running on the web server can combine HTML fragments stored with information retrieved from one database or another Site via RSS to produce a page that contains the latest information. Dynamic sites can be interactive using HTML forms, storing and reading back browser cookies, or by creating a series of pages that reflect the previous history of clicks. Another example of dynamic content is when a retail product retail site with a multimedia database allows a user to enter a search query, for example, for the Beatles keyword. In response, the content of the web page spontaneously change the way it looked before, and then display the list of Beatles products like CDs, DVDs and books. Dynamic HTML uses JavaScript to load the Web browser to interactively edit the content of the page. A means for simulating a certain type of dynamic web site, which avoids the loss of performance to initiate the dynamic engine on a user and by or for the connection, is to periodically regenerate a large number of static pages.