TwoUp is similar to "tiled windows" functionality available on other operating systems. TwoUp consists of four actions which can be performed on the frontmost application window: Left (move window to fill the left half of the screen), Right (move window to fill the right half of the screen), Up (move window to fill the top half of the screen), and Down (move window to fill the bottom half of the screen). These actions can be triggered via the TwoUp menu in the Mac menu bar or via system wide shortcuts. The default shortcuts can be triggered by holding the Control+Option+Command keys while pressing an Arrow key to indicate the direction you wish the window to go. The shortcut keys can be customized in the TwoUp Preferences.