A simplified structure of a biological neuron is given below. We can observe

• several inputs, the dendrites, and
• the axon as output.

The links between the axons of other neurons and its dendrites are called the synapses.

The stream received by a synapse is forwarded to the body of the neuron, and decreases according to the distance between the synapse and the soma, denoted synaptic weight. If the sum of the potentials coming to the soma (i.e. the somatic potential) exceeds a threshold, there is an emission of a potential of action (i.e. a "spike") through the axon.