Is it allowed to have several title tags in html?

Question

I was looking at the title tag http://www.w3schools.com/TAGS/tag%5Ftitle.asp So would it be legal if I had several titles with different lang IDs?

Answer 1

Simple answer: no. Only one (and exactly one) <title> element is allowed.

Source: e.g. XHMTL 1.0 Strict DTD:

Exactly one title is required per document.

Answer 2

No, HEAD does only allow one single TITLE element:

<!-- The TITLE element is not considered part of the flow of text.
       It should be displayed, for example as the page header or
       window title. Exactly one title is required per document.
    -->
<!ELEMENT TITLE - - (#PCDATA) -(%head.misc;) -- document title -->
<!ATTLIST TITLE %i18n>

Here’s the snippet from the document type definition of HTML 4.01:

<!ENTITY % head.content "TITLE & BASE?">

<!ELEMENT HEAD O O (%head.content;) +(%head.misc;) -- document head -->