γ-Butyrolactone (GBL) is a colorless, odorless liquid that is commonly used as a solvent in various industrial applications. It is a cyclic ester, specifically a lactone, and is known for its ability to dissolve a wide range of substances, making it useful in the production of plastics, coatings, and pharmaceuticals. In addition to its industrial uses, GBL is also a precursor to gamma-hydroxybutyrate (GHB), a substance that has both medical and recreational applications. Due to its potential for misuse, GBL is regulated in some countries, highlighting the importance of understanding its properties and effects.