**Abstract**

When any primary amine reacts with an aldehyde or a ketone under specific conditions, Schiff bases are formed. The general structure of Schiff base is R2C∙NR′ and is considered as a subclass of imines which is commonly used as a synonym for azomethine. The first imines were prepared in the nineteenth century by a classical method that involves condensation of a carbonyl compound with the help of amine under the distillation of azeotropic and to remove water formed in the system, molecular sieves are used. Later many ways of synthesis of Schiff bases are invented. Schiff bases exhibit a wide range of biological activities and are commonly used for industrial purposes. These are the most widely used as intermediates in organic synthesis, catalysts, pigments and dyes, polymer stabilizers, etc.

**Keywords:** Schiff bases, biological activity of Schiff bases, azomethine, Schiff base metal complexes, formation mechanism of Schiff base
