Today (July 4) is NOT the anniversary of the signing of the Declaration of Independence

Despite the annual proclamations that the fourth of July is the XXXth anniversary of the signing of the Declaration of Independence, the actual day of "declaration" and signing was July 2:

On July 2, 1776, the Continental Congress voted to declare that the 13 American colonies were independent states and no longer part of the British Empire. The next day, John Adams predicted in a letter to his wife, Abigail,

The second day of July, 1776, will be celebrated by succeeding generations as the great anniversary festival. It ought to be solemnized with pomp and parade, with shows, games, sports, guns, bells, bonfires, and illuminations, from one end of this continent to the other, from this time forward forever more.

He was mostly right about the celebration, but wrong by two days. After the vote, Congress spent the 3rd and 4th day of July fine-tuning and nitpicking the formal document that explained the reasons for declaring independence. Adams was also correct in that the vote was usually considered the significant event, and the post-vote follow-up was little more than paperwork. But for several after-the-fact reasons, that's not what happened.

Details at Neatorama.

Now that you know this, I suggest you remain quiet and don't tell anyone.  Be satisfied to be smug in your superior knowledge of American history, and don't go spreading this information to others at today's parties and celebrations, because people will just call you a smart-ass dick.  Just sayin'.