A sandwich has length and width. One can eat in the X or the Y directions. Whereas a hot dog has only length. You can eat it in only one direction. Therefor

A sandwich has length and width. One can eat in the X or the Y directions. Whereas a hot dog has only length. You can eat it in only one direction. Therefore a hot dog is actually just a degenerate case of a sandwich, where Y = 0. In other words, a hot dog is a one-dimensional or linear sandwich. We'll know humankind has entered a new age of enlightenment & prosperity when we invent cubic sandwiches.