Once the elements have been selected, the code can modify them, remove them, or insert new elements within them.
Modifying these elements could be as simple as adding or removing a CSS style, or changing the contents of the element.
The three client-side technologies you can use when implementing these techniques are HTML, cascading style sheets (CSS) and Java Script.
This chapter discusses how you can clearly define the roles of HTML, CSS, and Java Script on the client to ensure that developers and designers can work together without affecting each other's code.
This means that the same syntax you use in style sheets to select elements can be used to attach Java Script behaviors to elements.
Modification usually involves adding, removing, or updating the attributes and style classes applied to elements.
In some cases, CSS alone may be capable of performing the required changes, such as changing the style of hyperlink elements as the mouse pointer passes over them.
It is surprisingly easy to blur the lines of responsibility among the client-side languages.
For example, you might be tempted to use a CSS class to associate semantic or structural meaning to an HTML element.
Both hybrid and single-page interface (SPI) web applications that do not perform full-page post backs in order to change the rendered user interface (UI) must use client-side techniques for manipulating the document object model (DOM).