My company took away President's day as a holiday, but added Martin Lurther King Day. Discussing the change at a townhall, a senior business leader noted that no one knew which Presidents were being celebrated or when they died.
Presidents Day is celebrated on the third Monday of February. The federal holiday has traditionally honored George Washington who was born on February 22, 1732. The Uniform Monday Holiday Act of 1971 moved this holiday to the third Monday in February which can fall from February 15 to 21.
When I was a kid, both Washington's and Lincoln's birthdays were celebrated as separate holidays. Lincoln's birthday on February 12th was never a federal holiday; it was a California state holiday. California still lists Lincoln's Birthday as a holiday, but as of 2009 no longer gives State employees a paid holiday.