Federal Holidays
In the United States, there are ten (10) federal holidays set by law (5 U.S.C. §6103). Under current definitions, four (4) are set by date. If any of these falls on a Saturday, then Friday (i.e., the day before) may be observed as a federal holiday. Similarly, if one falls on a Sunday, then Monday (i.e., the day after) may be observed as a federal holiday.

New Year's Day January 1, 2008
Independence Day July 4, 2008
Veterans Day November 11, 2008
Christmas Day December 25, 2008

The other six (6) are set by day of the week and month.

Martin Luther King's Birthday Third Monday in January (January 21, 2008)
Presidents Day Third Monday in February (February 18, 2008)
Memorial Day Last Monday in May (May 26, 2008)
Labor Day First Monday in September (September 1, 2008)
Columbus Day Second Monday in October (October 13, 2008)
Thanksgiving Day Fourth Thursday in November (November 27, 2008)

General Election Day is not a federal holiday.

General Election Day First Tuesday after first Monday in November (November 4, 2008)