There will be celebrations honoring Patrick, the patron saint of Ireland, by more people around the world than could fit on the island to which he's credited with bringing Christianity.
Here's a quick look at St. Patrick's Day and everything green that goes with it.
What is St. Patrick's Day?
The first celebration of Patrick's life was an annual religious holiday held on March 17, the day it is believed that he died. The celebrations were feast days in honor of Patrick, who introduced Christianity to Ireland in the fifth century.
Who was St. Patrick?
Patrick was believed to have born in Roman Britain (Scotland), the son of a wealthy family. His name was Maewyn Succat. He was kidnapped when he was 16 and taken to Ireland as a slave. He escaped after, he said, God told him to run from his captors to the shore, where a boat would be waiting for him to take him back to Scotland. He fled, the boat was there and he headed home, but he didn't stay.
He returned to Ireland as a priest using the name Patrick. He worked there for the rest of his life to convert the Irish, who, at the time, practiced Celtic polytheism (Celtic paganism).
While he was never officially canonized, his followers regarded him as a "saint in heaven," thus he received a feast day from the Roman Catholic Church and the title of "saint."
How is it celebrated?
St. Patrick's Day is celebrated in various parts of the world. Until the 1970s, St. Patrick's Day was a religious celebration in Ireland, and the pubs in the country were closed.
Laws were passed then to open up the pubs for celebrations on March 17, and soon after, the country's leaders decided to market the holiday, highlighting Irish culture for tourism purposes.
The observance of St. Patrick's Day in Dublin, alone, has grown to a massive multiday celebration where around 1 million people take part.
In the United States, millions celebrate the holiday, whether they are of Irish descent or not. Two of the largest celebrations are in New York -- which hosts a five-hour parade -- and Chicago -- where city officials dye the river green.
Many people wear something green on that day, signifying a link to the color most associated with Ireland. Others lift a pint (or two) of beer at a pub or try corned beef and cabbage or Irish stew.
About that tradition of celebrating the day by eating corned beef and cabbage -- there's nothing more Irish than that, right?
About that tradition, well, we need to talk. Truth be told, corned beef and cabbage is about as Irish as a McDonald's Shamrock Shake.
What has become a tradition of eating corned beef and cabbage to celebrate St. Patrick's Day likely grew out of the fact that those foods were less expensive for immigrants who came to America. They substituted beef for pork and cabbage for potatoes.
OK, at least the snake story is true, right?
Sorry, but that's a bit of blarney, too. There were no snakes in Ireland, so Patrick didn't really have anything to drive out of the country, with the exception of the druids.
Some think the story that Patrick drove the snakes into the sea was really an allegory for him driving the pagan practices out of the country to make room for Christianity. Others say it just makes for a good bit of gab.
Let's say you want to impress your friends and throw out a few Gaelic phrases on Friday.
You will probably want to start with "Lá fhéile Pádraig sona dhuit!" That means "Happy St. Patrick's Day to you!"
It's pronounced: lah leh PAH-drig SUN-uh gwitch.
Native Irish speakers would shorten it to "Lá 'le Pádraig," a more casual way of offering good wishes on St. Patrick's Day. It's pronounced: lah leh PAH-drig.
If you want to impress your friends in a pub, you might want to throw out, "Pionta Guinness, le do thoil," or "A pint of Guinness, please." It's pronounced: Pyunta Guinness leh duh hull.
St. Patrick's Day by the numbers
There are 450 churches in the United States named after St. Patrick. Perhaps the most famous is in New York City.
It takes 40 pounds of dye to turn the Chicago River green for St. Patrick's Day.
According to the U.S. Census, 650,000 babies are named Patrick in a year.
A little more than 20 percent of the residents of Massachusetts say they are Irish; 20.6 of those in New Hampshire claim Irish ancestry.