A microprocessor is a general-purpose CPU that needs external DRAM and storage to work. That dependence raises cost, board complexity and power draw compared with a microcontroller, but it buys a different class of capability: hundreds of megabytes or gigabytes of memory, a full Linux or Android stack, standard networking and security libraries, and the ability to run containers or machine-learning models that would never fit on an MCU.
In IoT, MPUs show up in gateways, cameras, industrial HMIs, in-vehicle units and anything described as an edge device. The Raspberry Pi is the familiar example, though production designs usually use a system on module around a similar chip. Boot time of several seconds and milliamps of idle current make MPUs a poor fit for coin-cell products, so many systems pair one MPU with many MCU-based sensors.
Part of the IoT Glossary. Spotted an error or a missing term? Tell us.