Some weeks ago I read The lost language of cranes by David Leavit; leaving aside the mains topics of the book, it talks about the secret languages, signs, clues, etc which some collectives, people, etc use and they go unnoticed for other people.

In my case, as a cyclist, before take a ride I always look at trees or how some birds are flying, so I am able to know where the wind is coming, why I do that? In the outward ride I always go against the wind, so when I return, and so I am more tired, I have it on my back and I easier to come back.

Yes, there are some clues and signs that only have sense to our hobbies and routines.