كيف يعمل FET؟

Could you please explain in detail how a Field Effect Transistor, or FET, operates? I'm particularly interested in understanding the basic principles behind its functionality, including the role of the gate, source, and drain terminals. Additionally, could you elaborate on how the application of voltage to the gate affects the flow of current between the source and drain? It would be helpful if you could provide a simplified yet comprehensive explanation, as I'm still new to the field of electronics. Thank you for your assistance.