An skEdit bundle can specify a syntax highlighting dictionary. There are two types of dictionaries: element-based and keyword-based. Both allow you to assign a style identifier to certain fragments of text. This style identifier is later used to determine how to style the text fragments.
An element-based dictionary is for XML-like languages, such as HTML. It allows you to specify the style identifier used for elements, attributes, quotes, and comments. A keyword-based dictionary is for programmming languages, such as PHP. It allows you to specify the style identifier used for keywords, quotes, and comments.
How skEdit styles a file depends on which Theme you choose in the Colors pref pane. A theme assigns a foreground/background color to each style identifier, as well as colors for general document properties, such as the background and selection colors.