Not to be confused with something you would find at a fast food establishment, a hamburger menu—also called a collapsed menu icon or a hamburger button—is a navigational button typically used in mobile applications and mobile versions of websites.
The icon consists of three horizontal lines stacked on top of each other, hence the comparison to the appearance of a hamburger. The middle line resembles a hamburger patty, while the top and bottom lines look like a bun.
According to Gizmodo, Norm Cox created the hamburger menu in the early 1980s when he designed the graphical user interface for the Xerox Star computer workstation. Hamburger menus became popular with the rise of smartphones and tablets due to their value for improving user experience (UX). Unlike more traditional pull-down menus, hamburger menus take up a minimal amount of space—perfect for smaller devices with limited screen space.