The synaptic cleft is a small gap between two neurons, specifically between the axon terminal of one neuron and the dendrite of another. This space is crucial for the transmission of signals in the nervous system. When a nerve impulse reaches the axon terminal, it triggers the release of neurotransmitters, which are chemical messengers that cross the synaptic cleft to bind to receptors on the receiving neuron. Once the neurotransmitters bind to the receptors, they can either stimulate or inhibit the receiving neuron, influencing whether it will generate its own nerve impulse. This process is essential for communication within the nervous system and plays a key role in functions such as learning, memory, and muscle contraction.