Retailers open their doors Monday and roll out big sales to entice customers. Government employees -- along with kids -- have the day off. But do you know why?

The actual federal holiday is called "Washington's Birthday," after the nation's first president, George Washington.

According to the Gregorian calendar, adopted by England and its colonies after Washington was born, his birth date was February 22, 1732. (The Julian calendar has him born on February 11.) He is viewed as one of the greatest presidents in U.S. history and was also much adored during his lifetime.

It wasn't until 1885, though, that February 22 became designated a federal holiday to honor Washington.

In 1968, Congress debated whether to combine the two president's birthdays into one holiday, but decided against it. The legislative body passed the Monday Holidays Act that year, which said existing federal holidays would now be observed on Mondays to give government workers a long weekend.