Title bar and Menu bar
The Title bar, at the top, shows the name of the current spreadsheet. If the spreadsheet is new, then its name is Untitled X, with X being a number. When you save a new spreadsheet for the first time, you will be prompted to enter a name.
Under the Title bar is the Menu bar. When you choose one of the menus, a submenu appears with other options. The Menu bar can be modified, as discussed in Chapter 14 (Customizing OpenOffice.org).