The document discusses the differences between the presynaptic and postsynaptic sides of the synapse. Specifically, it notes that the presynaptic side contains calcium channels and synaptic vesicles filled with neurotransmitters, while the postsynaptic side contains ion channels with receptors for neurotransmitters. It then provides an overview of how neurotransmitters are released from the presynaptic terminal and bind to receptors on the postsynaptic membrane, allowing for transmission of signals between neurons.