[Jesus]

Also just for clarification: Tortas are not equal to sandwich in Mexico.
If you ask for sandwich you get two square slices of white box bread and something inside: mayonaise, mustard, onion, lettuce, tomatoe. Normally the options are: ham, cheese, tuna, ham and egg.

But if you ask for torta, you get a different kind of bread, the little son of a bagguette called bolillo or the fatso cousin called telera. Both of them are the size of a hamburger bun, but with a crusty shell (just like the bagguette wich in Yucatan is called Frances).
Inside, you normally will get a spread of re-fried beans on both inner halves of the bread, sometimes beans on one and mayonaise on the other. Tortas has more variates than sandwiches: pierna, jamon, huevo, chorizo, pollo, milanesa, pollo con mole, al pastor, romeritos, tuna, grilled fish, etc. joined by some lettuce, tomatoe, onion and in some places avocado or sauce or chiles en rajas.

So, torta is quite different from a sandwich. And in comparison with a Hamburger, the difference will be the bun, no ketchup, no picles and instead of just beef or chicken or fish, a lot more options and flavours.