One of the oddest aspects of Election Day in the United States is that there's no standard way for Americans to vote. Different states employ different rules on who can vote and when. What's more, voting technology can vary wildly.
For instance, this map from Mike Orcutt and VerifiedVoting.org looks at the different methods that voters in different states use to cast ballots. Some states, particularly in the Northeast, stick with paper ballots and punch cards. Other states have electronic machines with a paper trail that voters can review for themselves. Still others states, like Maryland and Virginia, use electronic machines with no paper trail: