The Open command loads a saved file, displaying the file's objects in their original state. It can be accessed from the File menu or the Toolbar.

When a file is opened with the Open as read only check-box filled (the default), the Save command and the Save toolbar button are disabled. This is done to prevent inadvertent changes to experiment files. The Save As command can be used to save the file under a new name. Clear the read-only box when opening a file if you want to be able to replace the file name.

You can create new documents with the New command.
 
 

Shortcuts:

    Toolbar: 

    Keys:
        Windows: CTRL+O
        Macintosh: O