Doctype Declarations

Developers can set the "document type declaration" or "doctype" of their Logi applications. Though it appears as the very first thing in an HTML/XHTML page, the doctype is not an HTML tag; instead it's an instruction to the web browser that identifies the version of the markup language the page is written in.

The following topics discuss the doctype options in Logi products:

• HTML5
• XHTML Strict
• XHTML Transitional
• XHTML Frameset
• What's the Impact?

About Doctypes

The HTML standards recognize a "document type declaration" (or "doctype") which is an instruction to the web browser that indicates which version of the markup language the page is written in. The doctype is a key component of standards-compliant web pages. Doctype tells modern browsers how they should apply HTML and CSS standards in rendering a page. These include more recent versions of Firefox, Chrome, Internet Explorer, Opera, and Safari. The doctype may include a URL reference to a Document Type Definition (DTD). The DTD specifies the rules for the markup language, so that browsers can render the content correctly. If an invalid, or no, doctype is specified in an HTML page, browsers go into "quirks" mode, where they each handle the markup in different and, possibly, outdated ways.

In Logi Studio, as shown above, the doctype is configured using the Doctype Declaration attribute of the General element in the _Settings definition. Five options are available using the pull-down selection list. HTML5isthedefault value if no DocType Declaration value is selected or entered. If None is selected, no doctype instruction is added to the HTML pages generated by the Logi Server Engine. The other four options are discussed individually in the following sections.