What are the differences between chubby, curvy, and plus size?

I've used these terms interchangeably in hopes of sounding complimentary but I've always wondered what the differences are, and what would make a man/woman one or the other. Or is it just self identifying?<br><br>Also, I'm assuming chubby is not the same as skinny fat. Or is it? <br><br>Thanks in advance.