Gnumeric can also be opened using a spreadsheet file directly. If there is a spreadsheet file on the desktop or in a file manager like Nautilus, it may be possible to click or double-click with the mouse pointer on the file and have Gnumeric open the file automatically. Alternatively, you may be able to right click on the file and get a pop-up menu that will allow you to select Gnumeric as the application to use to open the file.