What is the origin of "knock on wood". Is this just another myth legend?

When you say “or is it accomplished for good luck” then it is by definition a superstition.

One version (no one knows for sure) is that it derives from tree-worshipping cultures in which spirits inhabited trees.

I think, but I am not sure exactly, it goes back to when people would speak about something that should be unspoken. They would speak softly and knock on wood so others did not hear. I think it evolved to how it is used today.

I don’t know, but it is the one superstition I can’t seem to ignore even though I know it’s ridiculous.