CircuitPython is an open source programming language for microcontrollers and embedded systems based on Python! It is developed and supported by Adafruit. The language is a fork from micropython. There is excellent explanation of both CircuitPython and MicroPython at their respective gitHub repos below.
All development credit goes to the hundreds of contributors to those projects. As open projects, both invite collaboration and contribution and anyone can get involved through gitHub. You can get involved, follow the conversation and talk with the developers behind CircuitPython at the Adafruit Discord.
The main goal of CircuitPython is to be beginner friendly. I started teaching CircuitPython to my industrial design students at ArtCenter at the end of our Spring 2020 term. The language is indeed beginner friendly and much easier to learn (and teach) than Arduino and C++. As I delved deeper into teaching it however I missed the simple code references like those for processing or Arduino. I learned a ton with these resources in my early days coding for Arduino and Processing and missed the format and style of the reference when teaching CircuitPython. So in the spirit of the open source nature of the language I went ahead and created a reference myself. This is an Unoffical reference and as such should not be taken as authoritative on the language, its modules, or libraries. It is intended as a reference to help beginners read, understand and write code in CircuitPython.