Both interviews and surveys consist of questions devised by the researcher along with the customer's attempt to answer these questions. In terms of distinctions between the two, in the one, the questions are spoken, without too much "version control" (i.e. many differences in wording across interviews), while in the other, question wording is fixed. Another difference is that interviews are generally few in number, surveys many.
What else is similar across interviews and surveys, and what else is different?
(In your answer, please assume a self-administered web survey, and an in-person interview.)