Storage Components
Disk Physical Characteristics
The ABCs of Physical Addressing
•Sector
– A subdivision of a disk track which is created during formatting
– Typically a 512-Byte block – plus additional ECC Bytes
• ECC = Error Checking & Correction
• Head
– Read/Write head
– Can access a single disk surface
•Actuator
– Positions the Read/Write heads
• Track
– One revolution of the head over a disk surface
• Cylinder
– The information that can be accessed on a disk drive by all the heads,
without having to seek
– Can be considered as a series of concentric slices taken through the
disk platters