Having done my fair share of international travel, one of the things that always bothered me was the lack of information about what one needs to know when traveling abroad so I thought I'd put a few of the things I learned on (digital) paper in hopes of helping others.
With a few exceptions, the first thing new international travelers need to know is that in order to enter most foreign countries and more importantly, to return to your own country (without hassle), an international traveler must have a Passport.
For all intents and purposes a passport is a governmentally issued document that certifies the identity and nationality of the bearer. Without one, most countries will not allow entry - period. Fortunately this would be detected early on as most airlines won't even allow you to board to an international destination if you don't provide your passport. Passports may be obtained from your local Post Office or through various Passport services.
The second thing new international travelers need to know is that many countries require a Travel Visa from their country along with your passport in order to gain entry. A Travel Visa is an indication (in the form of a stamp or glued page placed in your passport) that the person is authorized to enter the country which issued the visa. Not all countries require this - but you must have one before you go if your destination country requires it. You can typically find this information on the Consular's website for the country you intend to visit.
The third thing every new international traveler should determine before they leave is if the destination country requires any types of special vaccination for travel. This may include the Yellow Fever Vaccinations, Hepatitis Vaccinations or several others. Make sure you know if your destination country requires one of these before you leave and get them well in advance (some can take months to complete) before you make travel plans. This info can also usually be found on the Consular's website of the country you intend to visit. Information can also be found on the travel cdc website.
International travel can be a fun and exciting experience but it can be soured quickly if you don't at the very least take the steps I've outlined above.
Imagine how disappointing it would be to take the time off from work, buy the tickets, get new clothes and luggage for the journey and fly all the way there just to have the agent at the boarder stop you and immediately send you home (at your own expense!). Sadly it happens all the time because people either don't know or understand their destinations entry requirements - so know before you go!