July 4, 2015 will be America’s 239th Independence Day, the day Americans celebrate our Declaration of Independence from Great Britain.

Here are five facts you should know about America’s founding document and the day set aside for memoration.

1. July 4, 1776 is the day that wecelebrate Independence Dayeven though it wasn’t the day the Continental Congress decided to declare independence (they did that on July 2, 1776), the day we started the American Revolution (that had happened back in April 1775), the date on which the Declaration was delivered to Great Britain (that didn’t happen until November 1776), or the date it was signed (that was August 2, 1776).

2. After the War of 1812, the Federalist party began e apart and the new parties of the 1820s and 1830s all considered themselves inheritors of Jefferson and the Democratic-Republicans. Printed copies of the Declaration began to circulate again, all with the date July 4, 1776, listed at the top. Celebrations of the Fourth of July became mon as the years went on and in 1870, almost a hundred years after the Declaration was written, Congress first declared July 4 to be a national holiday as part of a bill to officially recognize several holidays, including Christmas. Further legislation about national holidays, including July 4, was passed in 1938 and 1941.

3. The signed copy of the Declaration is the official,but not the original, document. The approved Declaration was printed on July 5th and a copy was attached to the “rough journal of the Continental Congress for July 4th.” These printed copies, bearing only the names of John Hancock, President, and Charles Thomson, secretary, were distributed to state assemblies, mittees of safety, manding officers of the Continental troops. On July 19th, Congress ordered that the Declaration be engrossed on parchment with a new title, “the unanimous declaration of the thirteen united states of America,” and “that the same, when engrossed, be signed by every member of Congress.” Engrossing is the process of copying an official document in a large hand.

4. John Hancock, the President of the Continental Congress at the time, was the first and only person to sign the Declaration on July 4, 1776 (he signed it in the presence of just one man, Charles Thomson, the secretary of Congress). According to legend, the founding father signed his name bigger than everyone else’s because he wanted to make sure “fat old King George” could read it without his spectacles. But the truth is that Hancock had a large blank space and didn’t realize the other men would write their names smaller. Today, the term “John Hancock” has e synonymous with a person’s signature.

5. The 56 signers of the Declaration did not sign on July 4, 1776, nor were they in the same room at the same time on the original Independence Day. The official signing event took place on August 2, 1776 when 50 men signed the document. Several months passed before all 56 signatures were in place. The last man to sign, Thomas McKean, did so in January of 1777, seven months after the document was approved by Congress. Robert R. Livingston, one of the five original drafters, never signed it at all since he believed it was too soon to declare independence.