HTML and CSS Reference
1) user retrieves Web
page from the server
2) user runs the program locally,
receiving instant feedback
Computing is thereby distributed so that the server is not overloaded with program-
related requests. Client-side programs also tend to be more responsive because users do not
have to wait for data to be sent over the Internet to a Web server. However, client-side pro-
grams can never completely replace server-side programming. For example, tasks such as
running a search or processing a purchase order must be run from a central server because
only the server contains the database needed to complete these types of operations.
In many cases, a combination of server-side and client-side programming is used. For
example, Web forms typically use client-side programs to validate a user's entries—such
as ensuring that all address information has been completely entered—and use server-
side programs to submit the validated form for further processing—such as sending a
purchase order to a central database. See Figure 10-6.