Microsoft Office 2007 has made changes to the interface from previous Office versions and has added some features.
Many of the significant changes to the interface are listed below:

Microsoft Office Button
The Microsoft Office Button replaces the File menu in previous versions of MS Office.
This button provides access to all of the previous File menu commands and some additional options.

The Ribbon

In Office 2007, menus and toolbars have been replaced by the Ribbon, which is organized by tabs, groups and commands

1. Ribbon Tabs are arranged across the top of the Ribbon. Each tab represents core tasks you may do in a given program
2. Ribbon Groups are sets of related commands displayed on the various tabs
3. Ribbon Commands are arranged throughout each Ribbon Group. A command can be a button, menu or a box where you would enter information

Dialog Boxes
Dialog Boxes offer a choice of commands to use. As in previous versions of MS Office, any command with an ellipsis (…) after the command name will open a dialog box. You may also open a dialog box by clicking on the arrow in the bottom right corner of certain Ribbon Groups. This arrow is called the Dialog Box Launcher.

Quick Access Toolbar
The Quick Access Toolbar allows you to customize a toolbar for easy access to commands.

Mini Toolbar
The Mini Toolbar appears when you select portions of your document and provides formatting options to apply to the selection.

Status Bar
The Status Bar shows information about the current state of your document such as page count, line number, etc. The Status Bar is customizable by right clicking on it.

Zoom Slider
The Zoom Slider provides a quick method of reducing or enlarging the view of a document.
Click on the plus or minus icons or, drag the Zoom Slider to customize your view.
Click on the percentage to provide a dialog box with view options.

Help Button
Clicking on the Help button provides access to Help and How-to topics for the application you are using.
You may also use the Search feature in Help to look for specific words or phrases.

Help and Training for all of the Office 2007 applications are available on Microsoft's website.