Processor: Micro:bit has a 32 bit Arm processor, which is an entry-level 32 bit processor. Arduino Uno has an Atmega328P, which is an 8-bit processor. Arduino h

Processor: Micro:bit has a 32 bit Arm processor, which is an entry-level 32 bit processor. Arduino Uno has an Atmega328P, which is an 8-bit processor. Arduino has 32k flash, 2k RAM, while Micro:bit has 512KB flash and 128kb RAM. That makes a big difference if you want to be able to run modern programming languages like Python or Javascript (much of anything beyond C), do numerics (e.g. robotics or control systems), etc. Peripherals: Micro:bit has built-in wireless, so you can have the talk to each other. It has microphone, speaker, accelerometer, buttons, simple display, etc. You can do a lot of things without any shields or extra hardware, and for most projects, you just need one. If I'm building a robot, I get a board which can control motors and servos. With Arduino, I need a whole pile of things. Lessons: Micro:bit also comes with very nice on-boarding for kids, and I do things with kids. Arduino is a half-dozen more steps of impedance. Are there higher-end boards under the Arduino brand? Yes. Do they share much of anything with Arduino beyond the name? Not really. If the pinout changes, the processor changes, and the only things which stays the same is the brand logo....