Wikipedia Reference Information
Fluid bearings are bearings which solely support the bearing's loads on a thin layer of liquid or gas.
They can be broadly classified as fluid dynamic bearings, hydrostatic or gas bearings. They are frequently used in high load, high speed or high precision applications where ordinary ball bearings have short life or high noise and vibration. They are also used increasingly to reduce cost. For example, hard disk drive motor fluid bearings are both quieter and cheaper than the ball bearings they replace.
The complete, up-to-date and editable article about Fluid Bearing can be found at Wikipedia: Fluid Bearing