F9 toggles the "Full Screen" mode on and off. With the Full Screen mode on, the Atlantis toolbars, scrollbars, document bar, status bar and rulers, all become invisible by default. To go back to the Atlantis normal working environment, simply press F9 again or press Esc. Note that you can choose which components of the Atlantis interface are displayed in the Full Screen mode. Use the View tab of the "Tools | Options..." dialog.
Document selections can contain whole cells and/or rows:
If you then press the Delete key or click the Delete 
button of the Edit toolbar
, you remove all contents from the selected cells/rows, but the cells/rows themselves are preserved as containers:
On the other hand, if you want to completely remove the selected cells/rows along with their contents, you need to press the Backspace key instead. With this result:
See also...
