A hotkey or a click on a tray icon starts the calculation dialog for your math formula. The dialog is generated out of the formula. Just enter the actual parameters and CalcExpress displays the result; it displays a small graph when a range is input; it rounds to the number of digits specified; it memorizes the last variable input and the position of the dialog. You can specify the appearance of background and button in the dialogs; and the icons used to represent the formula in the system tray. You can assign more than one formula to a tray icon then a menu pops up. CalcExpress displays the math formula in mathematical notation to allow for easy control.