The dialog HTML element is used to create a dialog box or window, such as a modal, that can be shown or hidden, providing interactive user prompts.

The div HTML element is a generic container used to group and style block-level content, serving as a versatile tool for layout and design.

The DOCTYPE declaration in HTML specifies the version of HTML used in the document, ensuring proper rendering and standards compliance by browsers.

The embed HTML element is used to integrate external content, such as multimedia or interactive applications, directly into a webpage.

The em HTML element is used to emphasize text, typically rendering it in italics, to convey importance or stress in a sentence.

The fieldset HTML element is used to group related elements within a form, enhancing organization and usability by providing a visual grouping and logical structure.

The figcaption HTML element is used to provide a caption or description for a figure element, offering context and explanation for the visual content.

The figure HTML element is used to encapsulate visual content, such as images or diagrams, along with their captions, providing a self-contained reference.

The footer HTML element is used to define the footer for a section or page, typically containing metadata, links, or copyright information.

The form HTML element is used to create interactive forms for user input, enabling data submission through various input controls like text fields and buttons.