I really enjoy eating the Mexican and Tex-Mex dish on large torittals. The burrito!
I love to make burritos and I stuff them with beef, beans, onion, tomatoe and cheese!
Those are my favorite fillings. Sometimes the shells are lightly gilled or steamed to make the more soft and easier to wrap. They are also easy to fold.
Yes and I learned on vacation that in Mexico, meat and refried beans are frequently the only fillings
Yes, but in the US we have more fillings like rice, lettuce, salsa, meat, cheese, and sour cream. 
Yes in the US burrito fillings may include Mexican-style rice or plain rice, boiled beans or refried beans, lettuce, salsa, meat, guacamole, cheese, sour cream
That's what I said. They can also be in different sizes and are sometimes very large!
Before the development of the modern burrito, the Mesoamerican peoples of Mexico used corn tortillas in 10,000 B.C. to wrap foods
The mesoamericans would also use filling like chili, peppers, tomatoes and mushrooms. 
The precise origin of the modern burrito is not known. Some have speculated that it may have originated with vaqueros, the cowboys of northern Mexico