I recall my mother making a purchase over $50 (fancy dress clothing) and the store had to call in for approval. When did magnetic stripes and swiping become ma

I recall my mother making a purchase over $50 (fancy dress clothing) and the store had to call in for approval. When did magnetic stripes and swiping become mainstream? How about calling cards. I believe I sat across from the man who "invented " the calling card as we knew it.