A: I haven't traveled much and need to know what I can carry in my luggage.
B: There are different considerations. You have to consider airline rules and rules for customs.
A: How do I find out about each country's Customs regulations?
B: You can go to a website for the particular country you are interested in.
A: Is there anything that I should keep in mind for all countries?
B: Do not ever lie about what you are carrying in your luggage. If you get caught, there is a major fine just for lying.
A: How about regulations for what you can carry on an airline?
B: The Internet is a good source for special regulations for particular airports and airlines.
A: I heard that I can't bring my own bottled water on the plane.
B: You can buy water at the airport once you pass luggage inspection.