Lubricating greases can be defined as solid to semi-fluid products of the dispersion of a thickening agent in a liquid lubricant: Commodity greases, usually based on lithium, calcium or sodium soaps (including some EP and lithium complex products) are general-purpose, low-cost products produced in large volumes.

High-specification greases, often based on a complex soap, are frequently manufactured with highly refined or synthetic base oils for more demanding applications than can be met with commodity grease products.