New from file
If you wrote or created an email message in another application (such as Adobe Dreamweaver), you can upload a .zip archive containing both the HTML and its referenced images, or just an .HTML file. The .zip may also contain files to be imported as attachments.
Type the subject line under the Subject field, write any notes for your reference, and drag and drop a file or browse to pick it from your computer. Click on Save. Once the message is saved, you can further work on it and make any final changes through the built-in HTML editor.
New from URL
Creating a new email from URL is used to retrieve the content (i.e. body text) of a webpage into your email message.