What does the term "favicon" refer to?

The term "favicon" specifically refers to a small icon that is associated with a particular website and is displayed in the browser's address bar, as well as in browser tabs and bookmarks. This icon typically helps users easily identify a website visually. It enhances the site's branding and can improve user experience by providing a visual cue, making it easier to locate a site among many open tabs or saved bookmarks.

The other choices do not accurately represent what a favicon is. An audio file is unrelated to visual branding and serves a different purpose, while a downloadable file pertains to content that users can obtain rather than an icon used for identification. Lastly, a security certificate relates to encryption and security measures for website transactions and is not an icon or visual representation of a website.