Bptt - What is the difference between backpropagation and BPTT?

The main difference between the Backpropagation and BPTT algorithms is how they are put into practice. If your RNs deal with sequential data, like as time series, BPTT is a way to extend the Backpropagation training method to them. Here, at each timestep, an RNN receives a single input and is expected to forecast a single output. In principle, BPTT works by unrolling each input timestep.