Arduinos are frequently used together with Raspberries. Arduinos have builtin support for analog I/O and can work on realtime tasks while the Raspberry may be under heavy load. This makes them useful for example when working with many kinds of sensors.
An easy way to program Arduinos is to use the Arduino IDE, since it can automatically install required cross-compilers, download libraries and can also be extended to work with boards other than original Arduino ones.
The steps below assume you have an Adafruit Trinket M0 board.
cd Downloads && tar -Jxvf arduino-1.8.13-linuxarm.tar.xz
cd arduino-1.8.13; ./arduino