XHTML by Example explains the differences in syntax between HTML and XHTML, and the concept of 'well-formedness', which is underused in HTML but crucial and required in XHTML. Further coverage includes authoring guidelines for a smooth transition to XHTML, XML DTDs and Schemas, and how they relate to XHTML, how XHTML modularization provides content to non-traditional browsers such as Palm devices, pagers, and cell phones, adding custom XHTML modules to standard XHTML, XHTML document profiling, and plans for XHTML 1.1. The final chapters cover advanced features, including Extended Forms, XHTML Basic, and Profiling content for different types of browsers.