This reprint explores the innovative field of surface coatings for functional materials, essential in energy storage systems, electronic devices, and medical implants. These materials often face challenges such as poor electrical conductivity and limited biocompatibility. Surface coating modifications have emerged as effective strategies to enhance their properties and meet modern technological demands. The contributors of this reprint share insights on various coating technologies, including metal oxides, ceramics, and conductive polymers, demonstrating their ability to improve the performance of critical components. For example, advanced coatings can enhance cycle stability in lithium-ion batteries and improve biocompatibility in medical implants. This reprint focuses on the design, fabrication, and optimization of surface coatings, examining their roles in increasing mechanical robustness and conductivity. Additionally, it addresses emerging trends and future directions in coating technology, providing valuable guidance for developing next-generation coatings across many different applications.