Comparing two documents side by side
This option allows you to display two documents
side by side on your screen, in order to compare them.
Make sure that the documents that you plan
to compare are both open and that the File tab is not active in both documents. You should be able
to see their names in the Switch Windows drop-down list in the Window group of the View tab.
Display one of the documents that you plan
to compare: in the View tab, click Switch Windows, then the name of the document to display, or click
the button relating to the document to display in the task
bar.
In the View tab, click the View Side by Side tool button in the Window group.
If only two documents are open, they will both
be displayed on your screen, one alongside the other.
If more than two documents are open,
the Compare Side by Side dialogue box opens for you to choose which document
you would like to view next to the current one.
Double-click the document that you would
like to see displayed next to the one that is already displayed,
or select it then click OK.
By default, when you scroll either document,
both documents scroll at once. If you wish to scroll each document
separately, go to the View tab in either document, Window, then deactivate Synchronous Scrolling 
.
If you have changed the size or position of
the windows, go to the View tab, Window group, then Reset Window Position 
.
When you have finished ...