Widows and Orphans

In typesetting, widows and orphans are words or short lines at the beginning or end of a paragraph, which are left dangling at the top or bottom of a column, separated from the rest of the paragraph. There is some disagreement about the definitions of widow and orphan; what one source calls a widow another calls an orphan.^[1][2] The Chicago Manual of Style uses these definitions:^[2]

Widow

• A paragraph-ending line that falls at the beginning of the following page/column, thus separated from the rest of the text.

Orphan

• A paragraph-opening line that appears by itself at the bottom of a page/column.
• A word, part of a word, or very short line that appears by itself at the end of a paragraph. Orphans result in too much white space between paragraphs or at the bottom of a page. 

http://en.wikipedia.org/wiki/Widows_and_orphans

How to Set the Widow/Orphan Control in Microsoft Word

Microsoft Word 2007
1. Open your document in Microsoft Word. If you have not started writing yet, you can set the widow/orphan control before you start. If you have already started writing, select all of the text before proceeding.

2. Select the "Home" menu. In the "Paragraph" section, click on the box to the right of "Paragraph." A dialogue box will appear.

3. Click on the "Line and Page Breaks" tab. Look for "Widow/Orphan Control" at the top, under "Pagination." Click on the box to the left. If there is a check mark in the box, the widow/orphan control is turned on and Word will make sure there are no single lines separated from their paragraphs. If there is no check mark in the box, the control is turned off.

4. Click "OK" when you have made your selections. Your paragraphs should now be set the way you wanted.

Microsoft Word 1997-2003
5. Open your document in Microsoft Word. If you have not started writing yet, you can set the widow/orphan control before you start. If you have already started writing, select all of the text before proceeding.

6. Click on the "Format" menu, then "Paragraph."

7. Click on the "Line and Page Breaks" tab. Look for "Widow/Orphan Control" at the top, under "Pagination." Click on the box to the left. If there is a check mark in the box, the widow/orphan control is turned on and Word will make sure there are no single lines separated from their paragraphs. If there is no check mark in the box, the control is turned off.

8. Click "OK" when you have made your selections. Your paragraphs should now be set the way you wanted.

http://word-en.blogspot.com/2013/02/how-to-set-widoworphan-control-in.html