Yup. Note that the method of specifically being fed the input sequentially, one by one, means that, for example, "Strings of odd length whose middle character i

Yup. Note that the method of specifically being fed the input sequentially, one by one, means that, for example, "Strings of odd length whose middle character is 'X'" does not comprise a regular language, even though one might naively reason this to be trivial to detect with O(1) memory ("Just go look at the middle character!").