Metasurfaces have emerged as game-changing technology ranging from microwaves to optics. This article provides a roadmap to the evolution of electromagnetic metasurfaces with a focus on their synthesis techniques, materials used for their design and their recent and futuristic applications. A broad classification is provided, and the design principle is elaborated. The efficient and economical use of available computational resources is imperative to work with state-of-the-art metasurface systems. Hence, optimization becomes an integral part of metasurface design. Several optimization methodologies reported to date have been discussed. An extensive study on the current research database gathered a comprehensive understanding of meta-atom topologies and the preferred fabrication technologies. The study concludes with a critical analysis and highlights existing and future research challenges to be addressed.