Covalent organic frameworks (COFs) are classified as lightweight, ordered, porous organic polymeric compounds. COF-based materials are comprised of the covalent bonds of lightweight elements, such as C, B, O, Si, and N, with structural units. They can be used in various industrial applications. There have been significant advances in the design and synthesis of covalent organic frameworks and their applications in gas storage, catalysis, adsorption, purification of small molecules, optoelectronics, molecular sensing, biomedical, targeted drug delivery, conductive membrane, and energy storage. COFs demonstrate fascinating optical and electrical properties. This review has endeavored to categorize and investigate the essential physicochemical properties of COFs for further studies and investigations.