It is very simple to use, just type in what you need to do and press the Enter key. The to do is added to the top of the list. You can bring to do's back to the top of the list by right-clicking them and selecting "Bring to top" from the menu.
The app resides in your menu bar (usually top right area of your screen) and can be accessed by clicking on its icon. Next to its icon is shown the number of to do's (this can be either all or uncompleted).
* It is not a reminder app, there are no alerts. It is a checklist.