I went to my attic today and took a few pictures. Here is one which shows the "dust" that covers most of the attic (as far as I could tell, it's all over). So I would imagine this is insulation, but I'm not familiar with such.
This looks like dust but lighter than dirt. I'm more familiar with things like that yellow bit we see in the background (I think a remain of some insulation used for the ducts that the builder probably left behind).
What I'm interested in knowing is how this is called and what it's made of. Anyone knows?
FYI: The reason I ask is that I was thinking to add cabled Ethernet connections (sockets) in all rooms. Only, I did not expect to find that material. Can it be safely dug/moved around which the cabling happens.
Note 1: The house is in the Sacramento, CA area.
Note 2: The house was built in 1983.