Composites or composite materials are engineered materials that consist of two or more constituent materials with wide discrepancies in their physical, chemical, and mechanical properties. The characteristic properties of these composite are as a result of the individual properties of their constituent parts and their respective volume fractions and arrangements in the material system. Depending on the intended application, composites can be designed to satisfy specific geometrical, structural, mechanical, chemical, and sometimes aesthetic requirements. Areas of application of these synthetic materials includes construction such as in buildings and bridges, automotive industry such as in car bodies, aeronautic, naval (e.g., ships and boats), and in the biomedical fields. Therefore, the main purpose of this paper is to introduce composite materials, epoxy resins their additives, fillers and discuss their current and potential use in coatings, electronic materials, adhesives, and matrices for fiber reinforced composites because of their outstanding mechanical properties, high adhesion strength, good heat resistance, and high electrical resistance.