A mode is a set of states of a system where user actions are interpreted differently from other modes. The term was originally coined for pre-GUI interfaces, such as the UNIX vi editor that had a typing mode (where keystrokes were copied into the document) and editing mode (where each letter invoked some action). In GUI systems modes are often related to the active window, or changes of meanings of icons. For example, some modal dialog boxes can take the keyboard focus when you are in the middle of typing leading to the typed text being ignored or misinterpretted.