Question

I do some coding in HTML, and was wondering what doc type header to use. How do I know if I am coding in HTML 4.0.1 Strict or HTML 4.0.1 Transitional? (or any other type)

Answer 1

You should choose DOCTYPE depending on the HTML tags that you use and your HTML writing style. Let me clarify that.

HTML 4.0.1 Strict – Basically allows zero style tags. For styling such pages you should only use CSS. Some tags that are not allowed in Strict: <center> <font> <u> etc. Also note that Strict requires closing tags for everything. You must use this:

<img .... /> <br /> instead of this: <img ... ><br>

Also in Strict all tags have to be nested correctly. Therefore, this style is cleaner and better formated. This makes it more reliable in the long run.

HTML 4.0.1 Transitional – Allows all those style tags and some other deprecated HTML tags. Also it does not require to use closing tags everywhere. In my personal opinion Transitional is really the lazy coders choice and should only be used in very specific situations.

You can read more about the differences between DOTCYPE’s here:

Converting XHTML transitional to HTML 4.01 strict

What is and what isn’t XHTML

Also read more about DOCTYPE’s from W3Schools here:

HTML !DOCTYPE Declaration

HTML HTML 4.01 / XHTML 1.0 Reference