Is IMEI the same as SN?

Hello there, I'm curious about a common misconception in the world of technology. Can you help me clarify whether IMEI and SN are indeed the same thing? I've heard them used interchangeably at times, but I'm not entirely sure if they serve the same purpose or hold the same significance. If they're different, could you explain the key differences between the two and their respective roles? Thanks in advance for shedding some light on this matter.