I mentioned before that there are colors we cannot see. The spectrum of light extends beyond the rainbow we know and into frequencies that only certain animals can see. But as it goes past that in both directions and further along that spectrum, it takes on a different character. Radio waves are a type of invisible very low-frequency light.
There are radio waves passing through your skull right now like light through water.
An artist named Nickolay Lamms visualized what wifi radio waves would look like, with different colors representing different wifi channels. If you could see wifi, it might look something like this: