So suppose you were given access to a machine to either view history or change it... what would you do? Or at least, see how things would have turned out if you did change the timeline.

For example:

Viewing- July 11th, 1804, Weehawken New Jersey. Specifically, the duel between Aaron Burr and Alexander Hamilton, so that I would know what really happened on that day... (Both as a history buff and a Hamilton fangirl.)

As for changing the timeline...

A lot of people would want to remove Hitler from the equation and prevent World War 2... but I'm aiming higher by preventing the assassination of Archduke Ferdinand, which started the First World War and indirectly lead to the Second.

So what would you all want to see or change?