Likes is the number of likes your story received. I.e. if 13 people liked your 1st chapter, and 1 person liked 2nd chapter, and 0 liked 3rd chapter, its 14 likes in total.
Views is number of clicks you attracted. It includes people who clicked on your story on sheer curiosity, and left afterwards, but also those who stayed and read your every chapter. It counts people who never made an account too, since it is the number of times your story was displayed.
Readers are the people who follow your story, i.e. the most accurate number of readers your story actually has. People don't have accounts, are lurking, and not receiving notification do not count there.