(X)HTML and CSS combine to provide users with static web pages, where they will always see exactly the same information every time they view the page. While this is appropriate in many situations, it does limit the usefulness of a web site. In order to provide dynamic web pages, we must add some form of scripting which builds the web page content “on the fly.”
We can provide this dynamic capability either on the client side, with the user’s web browser handling the creation of information as the HTML content of web page is rendered, or on the server side, where the page is built on the server as an HTML document and then sent to the user as fixed (static) information. The processes are similar from the user’s perspective — they rarely have any clue whether interactivity is produced locally or on the server.
Both processes typically use “scripting” languages, which are a form of programming language that is interpreted (translated into machine language and executed on a step-by-step basis without creating a separate executable file). Scripting languages also are quite flexible, allowing embedding of bits of program code into other file types. This allows a standard HTML file to additionally contain pieces of code that can be executed at the appropriate time to add changing information to a web page.
Readings and Assignment