Simplicity

Authors of web-based, expository mathematics should use technology appropriately. An author may be able to create a document that uses JavaScript or Java for navigation with fancy buttons, for example, but this is bad practice. Navigation is a basic feature of HTML. Using Java or some other sophisticated technology for this purpose limits the accessibility of the article and makes the article more fragile in terms of bugs or crashes. These costs come with no real benefit. On the other hand, Java is perfectly appropriate for an interactive mathlet that illustrates a mathematical concept in ways that are impossible with static text. To give another common example, it's bad practice to use a graphic image to simply display text; the information in the text is lost to processing software. In short, use the simplest technology appropriate for a given purpose.