Black stuff coming off on finger when I touch my scalp?

When I press a finger to my scalp, these little black things often come back (on my finger). They look almost like extremely small hairs (they're kind of like very short black lines). Does anyone know what this is and is this something to be concerned about? (Side-note: I wash my hair every day, so I'm not sure if it could be dirt or something like that.) I've always had a flaky, itchy scalp- could it be correlated? Could this be related to my hair loss (I have diffuse thinning). Thank you.

IF ANYONE WANTS TO SEE A PICTURE, I'VE ATTACHED ONE IN THIS OTHER FORUM:
https://patient.info/forums/discuss/...-scalp--584268

The black stuff looks similar to the stuff on the picture of the face wipe attached (I used this picture because you can only see them in a photo when they're concentrated together like that. On my finger they show up in much smaller amounts and more dispersed). Thanks