How can Bison and Buffalo be the same thing? they don"t even start with the same letter.....?

They do start with the same letter but which Buffalo are you talking about? The American Buffalo is the same thing as the Bison but there is also the African Water Buffalo which is a very dangerous animal. They are both bovines though same as our domestic cattle and eat basically the same thing. As a matter of fact the Native American tribes use to use the Bison much the same way as we use cattle except they used every part of the animal for some purpose or another.