**Abstract**

Our main focus is to report the tribological properties of ionic liquids (ILs). Mainly, lubricating of ILs has been reported to understand the applicability of ionic liquids (ILs) in petroleum-based lubricant industry and energy conversion process as oil additive. The influence of counter parts of ILs on tribological property has been reported for designing efficient lubricating and oil-additive property of ILs. The effect of halogenated and nonhalogenated ILs on corrosion is also reported during tribological studies at different metal surface. Further, role of ILs as oiladditive has been discussed in terms of better tribological performance. Structure modification and role of anion on better performance of tribological property have been mentioned for enhancing effectiveness of lubricant and oil-additive properties. Origin of corrosion and thin film formation on metal surface are also discussed in detailed using different types of ILs and metal surfaces.

**Keywords:** ionic liquids (ILs), tribological properties, halogenated and nonhalogenated ILs, lubricant, corrosion
