Chase the Electronart 1
basic electricity...
Electric current is actually created from electric and magnetic field strengths. Energy flux flows in a direction perpendicular to the electrostatic and magnetic fields producing what is defined to be electron current flow. Actual electrons migrate in a region and transfer motion to adjacent electrons. This generates the flux fields and energy transfers. Circuits require a return path. This path changes the potential energy produced by the voltage factor into current. The resulting flux fields leaving the power source and returning actually result in energy moving in one direction. The vector math substantiates this. The limiting factor in the impedance of the circuit.
This is a rather heady topic of physics to fully comprehend but as hobbyist working up fun projects and needing to understand these principles, we can simplify the results and avoid blowing up ICs or starting fires, something programmers rarely get to see.
Most textbooks simulate electron flow as a fluid in a pipe, pushed by voltage
pressure, restricted by material resistance. Once the various factors are adjusted
to represent the results seen, it doesn't really matter in a practical sense
until you reach very high frequencies or encounter large inductive/capacitive
influences to your circuit. Thus Ohm's law is a practical result of E = I x R,
where E is electromotive force, I current in amperes, and R is the resistance of
the material in ohms the current is traveling through. Keep in mind, the energy going
through the elements of a circuit is getting there via the flux fields generated
by this electromotive phenomenon.
Where things get dicy is with alternating currents. Frequency ups the game and the flux fields reach out to find capacitances and inductances. Interference among circuit components, reflection of pulsed energy, and signal degradation. Circuits begin to delay rise-times and fall-off time. When current finds an inductor, the voltage developed by the inductor's impedance rises exponentially so there is a delay in the current compared to the voltage. The opposite is true of capacitors. The current instantly appears on the device but the voltage builds with a delay. Ultimately, a circuit has to contend with series and parallel paths of resistance, capacitance, and inductive effects. Resonances occur, inductive coupling, static discharges, all too interesting not to study up a bit.
As frequency rises in a conductor, the electron motion start to generate magnetic fields counter to main flux field moving energy down the wire and electrons tend to push towards the outer surface of a wire. This is known as the skin effect. The impedance of the conductor goes up do to this and is know as an eddy current. Motors and transformers are particularly impacted, which causes heat losses.
So here's your challenge. Check out the references below, get interested in the the basics and you'll be motivated to maybe study electrical engineering. Can't be all that bad.