The flow of information within a neuron is , whereas the flow of information between neurons is .

The flow of information within a neuron is intracellular signalling whereas the flow of information between neuron is inter cellular signalling.

Explanation:

Central nervous system consist of 2 types of cell that are neurons and glia where neurons are the information processing structure in Central nervous system.A typical neuron consists of 4 parts called- cell body,processes,dendrite and axons.Cell body is the metabolic controlling center and from cell body, processes structure is extended which conduct signal flow to or away from the cell body.Dendrites receive the incoming signals and the outgoing signals to the other neurons are flow along with the help of axons.Neurons have an unique features  of intracellular and inter cellular signalling.Intracellular signalling is proceed within the cells and inter cellular signalling is is transmitted between the cells.The communication that is generated between the neurons are achieved by synapses.This process is called as neurotransmitter.

This post might have the info you need: