Given the information in the previous section we can draw up a matrix as follows to represent various possible scenarios for which we will need to declare the character encoding differently.

Reading across the top: the character encoding can be declared in the HTTP header, the XML declaration or a meta element. We will explain these approaches in more detail in a moment.

Down the side: we may be dealing with HTML, XHTML served as HTML (text/html), or XHTML served as XML.

We will now look at which combinations are most appropriate, and complete the table to summarize at the end of this section.