Models of biological and artificial neurons.

(a) Simplified model of a biological neuron: The main body of the neuron receives input from many other neurons, transmits (or not) a signal which is then sent to many other neurons. (b) Model of an artificial neuron in a neural network. Input is received from other neurons or the outside world in the input layer, the computed output is transmitted to other neurons or the outside word for the output layer. (Image in (a) published with a CC0 license at https://pixabay.com/en/brain-neuron-nerves-cell-science-2022398/).