Typical length 2400 feet. Each physical write to tape is followed by a gap which is typically .25 inches in length. Magnetic Disks Information is organized on concentric circles called tracks. If more than one platter, the tracks are organized into cylinders. Tracks are divided into sectors.
Transfers start at beginning of sectors.
Typical capacity 2 to 9 gigabytes. Floppy Disks See Figure 2-17 for typical times. Meg Detector measures energy off surface when laser is shone.