It is deeply wild that the “hello world” project of arduino like systems is to on-off modulate a ~500 THz electromagnetic wave emiter. (Aka blinking an led)
Also that if you want to emit in the mhz range you need permissions and specialist equipment, but in the ~500 THz range you can just use a sub-dolar part and go ham with it without needing to be a ham.
It's high time that we start regulating terahertz EMF radiation. It is dangerous stuff. It can even cause physical eye damage! Scientists refer to it as "pollution" when it occurs at night, because it's so unnatural for the human body to be exposed to so much of it after dark.
The fact that THz EMR is completely unregulated and never discussed by the media is a sign that politicians and the scientific community are complicit in protecting industry at the expense of people's health.