What is the difference between BFT and PBFT What are the differences between BFT and PBFT?

I want to know the difference between these two concepts.

If there is any improvement in the BFT's limitations, let me know.

Please answer. Thank you.
BFT is a class of problems where a group of nodes needs to find consensus, where some of the nodes may be malicious. PBFT is an algorithm that generates consensus in one of those environments (specifically with signed messages and partially sychronous network). An good writeup is here: https://medium.com/s/story/lets-take-a-crack-at-understanding-distributed-consensus-dad23d0dc95