When dtNotes is launched, the program icon appears in the system tray:
If you right-click this icon with your mouse, you will see a menu that can be used to see notes list, create new note, or launch program settings window. You can also set a custom function that will be triggered when you double-click the icon (the option is called "On tray icon double-click" and is located in the program settings window). For example, you can set the program to create a new note when you double-click the icon.
If you left-click the icon with your mouse, you will see a list of notes you recently worked with. The number of notes there can be customized in the program settings window.