Datasheet

Start your journey with Microsoft MakeCode block-based or Javascript
programming. Then, you can use the same board to try CircuitPython,
with the Python interpreter running right on the Express. As you
progress, you can advance to using Arduino IDE, which has full support
of all the hardware down to the low level, so you can make powerful
projects. You can even use code.org CS Discoveries to learn all about
coding right in your browser!
Because you can program the same board in 4 different ways - the
Express has great value and re-usability. From beginners to experts,
Circuit Playground Express has something for everyone. If you are
looking for the original, Arduino-only Circuit Playground, check out the
Circuit Playground Classic.
The board is round and has alligator-clip pads around it so you don't
have to solder or sew to make it work. You can power it from USB, a AAA
battery pack, or with a Lipoly battery (for advanced users). Circuit
Playground Express has built-in USB support. Built in USB means you
plug it in to program it and it just shows up, no special cable or adapter
required. Just program your code into the board then take it on the go!