The poem is often called by the start of its first line; the poem begins as follows:
'T was the night before Christmas, when all through the house,
Not a creature was stirring, not even a mouse;
The stockings were hung by the chimney with care,
In hopes that St. Nicholas soon would be there;
The children were nestled all snug in their beds,
While visions of sugar plums danced in their heads,
And Mama in her 'kerchief, and I in my cap,
Had just settled our brains for a long winter's nap-
When out on the lawn there arose such a clatter,
I sprang from the bed to see what was the matter.
A version of the entire poem as it was originally printed can be found online. New books containing the poem come out nearly every year. The two you see here are two of my favorites in recent years, but there are truly versions for everyone.
But I don't just want to talk about the poem as it exists; I'd like to talk also about the many parodies this poem has inspired.
A parody poem is, as one might guess, a poem that is a parody (or send-up) of another existing poem. For instance, in Alice's Adventures in Wonderland, Lewis Carroll includes a parody of "Twinkle, twinkle, little star", when he has the Mad Hatter recite the following (which he breaks off unfinished, lest you think I got lazy):
Twinkle, twinkle, little bat!
How I wonder what you're at!
Up above the world you fly,
Like a teatray in the sky.
Parodies of A Visit from St. Nicholas abound. There appear to be versions for nearly every fandom: there's a Star Trek (TNG) version, "Twas a Star Trek Christmas, a Dr. Who version, "The Night Before Christmas, on the Tardis, an homage to the work of H.P. Lovecraft, a NASCAR Christmas, a LOTR "Middle Earth" version, and more. In fact, some guy has put together a Canonical List of Twas the Night Before Christmas Parodies that should kick up something for nearly every interest - and then some.
The first line of the poem sparked not only the title of The Nightmare Before Christmas, but the original idea, which was a three-page poem written by Tim Burton based on A Visit from St. Nicholas, How the Grinch Stole Christmas, and Rudolph, the Red-Nosed Reindeer. It has also made its appearance in comics (including Garfield and Fox Trot), comix (issue 40 of DC Comic Young Justice was devoted to the poem, which involved Santa v. an alien, and the Winter-Een-Mas webcomix at CTRL+ALT+DEL), movies (including Die Hard and National Lampoon's Christmas Vacation), and television shows (including Friends, Animaniacs, and Danny Phantom). To say nothing of the parody The Night Santa Went Crazy by Weird Al Yankovic, animated by Nicklaus Liow.
He sprang to his sleigh, to his team gave a whistle,
And away they all flew like the down of a thistle,
But I heard him exclaim, ere he drove out of sight,
“Happy Christmas to all, and to all a good-night.”