Use the following format to indicate a date: month day, year, as in July 31, 2010. Do not use day month year or an all-number method. Do not use ordinal numbers to indicate a date.

Microsoft style

February 23, 2011

June 11, 2007

Not Microsoft style

23 February 2011

6/10/11

11/6/07

April 21^st

When a date appears in the middle of a sentence, set off the year with commas.

Microsoft style

The February 23, 2011, issue of the New York Times ….

Not Microsoft style

The February 23, 2011 issue of the New York Times ….

The February 23 2011 issue of the New York Times ….

To indicate a month and year only, do not use commas.

Microsoft style

The February 2011 issue of MSDN Magazine ….

Do not use abbreviations of months unless necessary to save space. If you must use abbreviations, use three-letter abbreviations: Jan., Feb., Mar., Apr., May, Jun., Jul., Aug., Sep., Oct., Nov., and Dec.