When voters walk into a busy polling place on election day, they see a vast array of people, most of them rushing around, doing lots of different things. Who are these people and what is their function in the election? Besides (hopefully) lots of other voters waiting to vote, you'll see:

Poll workers:
These people are here to help you vote. They check voters in, making sure they are registered to vote and are at the correct polling place.

They hand out ballots and show voters where to deposit their ballots after voting. Perhaps most importantly, poll workers can show voters how to use the particular type of voting device being used. If you have any problems using the voting machines or are not sure how to use the machine to complete your ballot, by all means ask a poll worker.

Poll workers either volunteer, or are paid a very small stipend. They are not full time government employees. They are people who are donating their time to help make sure elections are conducted fairly and efficiently.

If you run into any problems while voting or waiting to vote, ask a poll worker to help you.

Election judges:
At most polling places, there will be one or two election officials, or election judges. Some states require one Republican and one Democratic election judge at each polling place. Election judges ensure that the election is conducted fairly. They settle disputes over voter qualification and identification, deal with damaged and incorrectly marked ballots and take care of any other issues involving interpretation and enforcement of election laws.

Election judges officially open and close the polling place and are responsible for the safe and secure delivery of sealed ballot boxes to the vote counting facility after the polls close.

Observers or poll watchers:
A limited number of observers representing the political parties will be allowed in each polling place. They are there to make sure that the vote is honestly taken and that their party is not being cheated. Observers are strictly prohibited from endorsing their party's candidates or from seeking votes.

Other voters:
Hopefully, you will see many other voters inside the polling place, waiting their turn to vote. Once inside the polling place, voters may not try to convince others how to vote. In some states, such "politicking" is prohibited both inside and outside within a certain distance of the doors of the polling place.

Exit poll takers:
Especially at lager precincts, exit poll takers, usually representing the media, may ask people leaving the polling place which candidates they voted for. Voters are NOT required to respond to exit poll takers.

Also See:
Election Day Q&A
If You Make a Mistake While Voting
Counting the Votes
Why Many Americans Fail to Vote
Registering to Vote