The Transportation Security Administration (TSA) provides guidelines for carry-on luggage on their website. Different airlines, such as Delta and United, also publish website luggage guidelines.
The TSA website guidelines for carry-on items includes information on liquid sizes, prohibited items, food and gifts. These guidelines may differ depending on whether the traveler is flying nationally or internationally. The United States Department of Homeland Security and the United States Department of Agriculture provide regulations on bringing food or animal items into the United States on flights from foreign countries. Travelers may visit the U.S. Customs and Border Protection website to read about these regulations.