This book serves as a guide for students, researchers, and faculty members in the field of metamaterials-based devices, presenting recent advances and trends in this subject. The book comprises a total of five chapters, providing in-depth knowledge on numerical methods and the various properties and applications of metamaterials. The significant applications considered are metamaterial-based absorbers and communications devices. Each chapter comprises a detailed background on the considered application, recent work in the area, a possible solution, and future aspects.