The signals in a feedforward model only move in one way, to the output layer. With zero or more hidden layers, feedforward networks have one input layer and one single output layer. Pattern recognition makes extensive use of them. The recurrent or interactive networks in the feedback model process the series of inputs using their internal state (memory). Signals can move in both ways through the network's loops (hidden layer/s). They're commonly utilized in activities that require a succession of events to happen in a certain order.