Many projects you create with the Office suite will consist of more than one document.  You might use Word to create a report, Excel to produce a spreadsheet which is mentioned in the report, and Powerpoint to prepare a presentation for the Board.

Once the project is complete, it would be very convenient to save these three documents in a single 'meta-document' so that you can find them all again later.  This is what the 'Binder' does - and quite a lot besides.

Step by step:

Create a new Office document, and when asked what kind of document you want, select Blank Binder.

Binder refers to each document it contains as a 'Section'.  Initially, the Binder is empty, and so to add a document, select the Section/Add file... menu option.  Browse to your documents folder and select the document you wish to add to the Binder.  Finally, click the 'Add' button.  Your Binder might now look like this:

In the left pane is an icon of the document, while the contents of the document appear in the right hand pane.  You can add any Office document to the Binder in this fashion.  Sometimes adding a document to a Binder can take quite a long time, because Word has first to open the application which created the document.

Notice that the menus have changed somewhat.  The FILE menu now reflects the fact that we are dealing with a Binder, not simply a Word document, while a new menu (Section) has appeared.

You will want to exert some control over how your Binder behaves, so under the File menu, select Binder Options...  The following Dialog box appears.

This allows you global control over your Binder.

Finally, since one of the main reasons for creating a binder is so that you can print out the entire project as a single entity, you need to familiarise yourself with the print settings

NB
Documents added to the Binder are EMBEDDED, not LINKED.