This paper has presented an introduction about Metamaterials and their scope in the fields of optics, and engineering. In recent years, there has been a growing interest in the fabricated structures and engineered composite materials that have new, physically realizable response functions and properties that do not occur or may not be readily available in nature. In the last decade, a new research area based on the study of Metamaterials has emerged. There is not an absolute definition of Metamaterials but this word is a combination of “meta” and “material”, which means something beyond, changed or something advance, and the most commonly used is that they are artificial materials made of a periodic arrangement of unit cells and have negative refractive index and referred to as left-handed materials. Metamaterials are expected to have an impact in the field of optics as well as in the field of engineering. Metamaterials are used as antenna, sensor, and absorber and in Metamaterial and there is no research is possible without the development in the fabrication structure. Metamaterial have a negative refractive index and due to this property metamaterial causes light to bend in unusual ways, and come back out the same way it went in, and invisible cloak may be constructed in future.