Hamburger button

The hamburger button (the triple bar ≡ or trigram symbol ☰), so named for its unintentional resemblance to a hamburger, is a button typically placed in a top corner of a graphical user interface. Its function is to toggle a menu (sometimes referred to as a hamburger menu) or navigation bar between being collapsed behind the button or displayed on the screen. The icon which is associated with this widget, consisting of three horizontal bars, is also known as the collapsed menu icon.