You’ve just met the four most essential players on the electronics team: resistors control the flow, capacitors and inductors manage the energy, and transformers safely change the voltage. Every complex gadget you use, from your phone to the power grid it charges from, relies on these fundamental principles. Mastering their unique roles is your first, most powerful step into the incredible world of circuit design. Keep building on this foundation, and you’ll be amazed at what you can understand and create.