The world is a pretty big place. It's estimated that there are more than 7 billion people in 196 different countries, all with different types of cultures, beliefs and customs.
Something you do on a daily basis here in the U.S. can be a major no-no in other places.
When traveling internationally, don't commit any cultural faux-pas. Check out the Ultimate Guide to Worldwide Etiquette before you go. It has cultural tips for 29 different countries spread across the globe.
Just click on the country you are visiting to get started. You will see how much to tip when you go out to eat, complete with dining dos and don'ts.
You will also see how to greet people that you meet and other cultural quirks that you will need to pay attention to, such as taking off your shoes before entering a house in Japan.