I don't know anything about Haskell other than the basics. I've played around with it, but the most "complicated" things I made with it was Fibonacci and factor

I don't know anything about Haskell other than the basics. I've played around with it, but the most "complicated" things I made with it was Fibonacci and factorial functions. I'm pretty curious, can someone summarize for me, what was the deal with FTP? What are the pros and cons, and why are people upset about it? That'd be really nice, thanks.