Here is a set of very basic pages using several DOCTYPES that can be used as a reference for the declaration, content-type headers, or whatever you might need.
Each of these DOCTYPE examples are configured to response with the appropriate Content-Type HTTP Header as recommended by their respective W3C specifications. The Content-Type for each examples is as follows:
- HTML 4.01 Transitional - text/html
- HTML 4.01 Strict - text/html
- XHTML 1.0 Transitional - application/xhtml+xml
- XHTML 1.0 Strict - application/xhtml+xml
- XHTML 1.1 - application/xhtml+xml
- XHTML 2 - application/xhtml+xml