Arduino, MicroPython and Raspbian (recently relabeled as Raspberry Pi OS), just to name a few, have spawned a plethora of low-cost microcontroller boards. In most cases, you can purchase one of these inexpensive evaluation boards for much less than you can build a similar platform from scratch.
Many of the microcontroller boards uniquely target a particular flavor of Arduino. For instance, the Teensy family of development boards are designed to run against a programming system called Teensyduino. Under the covers, the Teensy hardware is based on a basic implementation of the MK20DX256VLH7 ARM microcontroller. The Teensy also sports an on-board +3.3VDC regulator. The inclusion of the on-board power supply makes the Teensy ripe for reuse. In this course, we will ween the Teensy away from its dependence on Teensyduino and prepare it for development with Embedded Studio.