The neurons are grouped listed here layers: 1 input layer, n hidden processing layers and one outputlayer. In a feedforward network each one neuron in any single layer provides only directed to connections to the neurons of the next layer. Feedforward network:-The neuron layers of a feedforward network are clearly separated: One input layer, one output layer and one or more processing layers which are hidden from the outside (also called hidden layers). Connections are just permitted to neurons of the following layer.Some feedforward networks permit the called shortcut connections.