Similar: Fatty acids are generally long chains of hydrocarbons with a carboxylic acid group at one of the ends. While Lipids are polymers of fatty acids with a nonpolar hydrocarbon chain and a small polar oxygen group.
Different: Fats are actually a type of lipid. Lipids are a major class of biochemical compounds that includes oils as well as fats. Organisms use lipids to store energy and for many other uses. Lipid molecules consist mainly of repeating units called fatty acids.
