The Arduino IDE is the software package we use to modify the code on the board that controls the LEDs. It is available for all major operating systems, so it shouldn’t matter if you use a Mac or Windows PC to program the board.
To download the software, go to https://www.arduino.cc/en/Main/Software and choose your operating system from the list, and follow the instructions. Once it is started, we can connect to the board and start programming!
Alternatively, we don’t even need to install the software anymore, because we can use the online editor! Found at https://create.arduino.cc/editor, this browser-based IDE means that we don’t have to install the whole software package if we don’t want to. There are some tradeoffs, but it works very well.