Photos: Dissecting a hard drive

Once the main part of the disk is opened, all of the most important pieces are on display. On the left is the head disk assembly, which contains a round platter where data is stored and read via the triangle-shaped mechanical arm and head.

Western Digital adds the yellow piece in the top right corner, called a ramp, which holds the mechanical heads in place and away from the platter when information is not being read or written. This helps protect the heads and the data stored on the disk from being corrupted if the disk, or the notebook it is inside of, is ever dropped or bumped.

The inside of the lid, on the right, is equally important to the proper functioning of the drive. The grooves and glue are contoured to create airtight seals to keep out all dust and particles that will scratch or contaminate the disk.

The white capsule is the carbon pouch, which acts as an air filter. Inside is a carbon pellet that sucks up any dust. The white material it's encased in is GoreTex, specifically chosen for its ability to allow air to move freely through it--but not moisture, which can be deadly to a mechanical hard drive.