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Glossary

HTML doctype

An HTML doctype (document type declaration) tells your reader’s email client they should expect an HTML document, written in a particular version of HTML that contains specific coding languages or characteristics. This information is contained in a doctype declaration contained in the <head> of your HTML email template.

Here are a few doctypes you can use in your HTML email:

HTML 5
HTML 4.01: Strict, Transitional, or Frameset
XHTML 1.0 Transitional

These all shine in different areas. However, we recommend using the HTML5 doctype declaration .