Quoting the Tag-Wiki:
An HTML form is a section of a document containing normal content, markup, special elements called controls (checkboxes, radio buttons, menus, etc.), and labels on those controls.
Users generally "complete" a form by modifying its controls (entering text, selecting menu items, etc.), before submitting the form to an agent for processing (e.g., to a Web server, to a mail server, etc.)
I find asking myself: What context does this provide in a question? What benefit does that tag have?
Does it imply something that html doesn't?
In short: Why do we have that tag?