Bit near centre of rotating disk passes fixed point slower than bit on outside of disk
Increase spacing between bits in different tracks
Rotate disk at constant angular velocity (CAV)
Gives pie shaped sectors and concentric tracks
Individual tracks and sectors addressable
Move head to given track and wait for given sector
Waste of space on outer tracks
Lower data density
Can use zones to increase capacity
Multiple zone recording
Each zone has fixed bits per track
More complex circularity