Style sheet
 
A collection of styles used to format a document.
You apply the styles in a style sheet to your
document to guarantee the uniform appearance and
positioning of the text. Styles may be changed,
and the applied styles will automatically adjust
the document text to reflect the changes. You can
view, create, revise, and attach a style sheet
with the style sheet commands on the Format menu.
Word provides a default style sheet, NORMAL.STY,
that determines the default styles for Word
documents. You can customize the NORMAL.STY style
sheet with the Format Define Styles command. Each
style sheet is a separate file that ends with the
filename extension .STY.