This lecture introduces the construction of single cell electrical models using NEURON. It covers the basics of creating a neuron with one compartment, setting its length and diameter, calculating surface area, defining capacitance, running simulations, recording membrane voltage, injecting current, and adding transmembrane currents. The instructor explains the NEURON Python module, the structure of a cell in NEURON, the importance of default units, and the integration of equations over time. The lecture concludes with the insertion of the 'hh' mechanism to model transmembrane currents and the setting of conductance and reversal potential values.