Ahhhh, you've touched on an odd bureaucratic holiday. Both Lincoln and Washington were born in February. We used to celebrate both men's birthday, on the actual day of birth. It was a minor celebration, mainly posters in school, and plays, no real holiday.
Then the bureaucrats got involved. They schemed to combine the two into one celebration, and then rename it, so as to pretend to be all inclusive of all presidents. Thus, it became presidents day, and was designated a national holiday. So, government workers get the day off, and the rest of us keep trying to make a living so we can pay the government workers.
(In November, as me about Veteran's Day, that one gets me going since I'm a Veteran who routinely works that day while the government workers that that day off too!)
I don't work for the Government, but it is one my company's few paid holidays. I wonder if it is a state-mandated thing here in California.
We also have one floating holiday we can use whenever we like (we only get 1 day off for Thanksgiving). Some people use it for MLK, others for Veteran's Day--I usually use it to make Christmas a longer vacation.
That was the best pithy explaination of President's Day.