""Relationship of Disk Head, Disk, and Contaminants" Graph showing a side/cutoff view of hard drive reading head over the platter, with size comparisons: * Space between the head & platter: 100µ * Smoke particle: 250µ * Fingerprint smudge: no unit but it's drawn twice as big as the smoke particle * Lint & dust: no unit either, 4 times bigger(ish) than the smudge * Humar hair: .004" The oxide layer on the disk is 200µ wid