Can you tell me the difference between correspondence, part-time and distance courses?

Correspondence, Part time and Distance learning are designed for working professionals to continue their education and obtain degrees of their choice while working. Education by correspondence is when institutes provide all reading materials to students. Students learn themselves, submit assignment

PART TIME: This is a sort of program designed for software professionals. People can go to colleges to attend classes after their working hours. DISTANCE EDUCATION : Distance education and Correspondence are same. You may refer to below link https://ask.shiksha.com/getTopicDetail/1102282/What-Is

I think that all are similar practically and they imply no direct attendance before the Teacher. But, a teacher is always needed in one way or other, for all of us.