Microsoft Word can help you determine whether formatting is applied inconsistently in your document. For example, if most of your headings in a document are 48 point, but you accidentally formatted some as 47 point, Word can help you format them all as 48 point. Consistent formatting can give your documents a more professional look.
Word checks for the following formatting inconsistencies:
If two occurrences of formatting are markedly different, then Word will not designate them as inconsistent. For example, occurrences of Arial, 12 point and Arial, 16 point would not be considered inconsistent, since one might be used for body text and the other for headings.
When you turn this option on, Word checks for inconsistencies as you type; the inconsistencies are marked with blue, wavy underlines.