The HTML Aside Element (<aside>) represents a section of a page that consists of content that is tangentially related to the content around it, which could be considered separate from that content. Such sections are often represented as sidebars or as inserts; they often contain side explanation like a glossary definition, more loosely related stuff like advertisements, the biography of the author, or in web-applications, profile information or related blog links.
Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.