This review systematically examines various Humidification-Dehumidification desalination systems, focusing on their essential components and operational efficiencies. Our study confirms the viability of seawater desalination using these systems, particularly for decentralized applications. Among humidifiers, the packed bed type is predominantly utilized due to its effectiveness. Direct dehumidifiers are shown to enhance system performance significantly compared to indirect types. Hybrid energy systems demonstrate superior efficiency, achieving the highest gain output ratios, while solely thermal-based systems are less efficient. Comparatively, systems incorporating solar water heating surpass those using solar air heating in output. Optimization of system productivity and economic efficiency is achievable through integration with a heat pump, maintaining low costs while enhancing the gain output ratio. Critical design parameters influencing freshwater production include the feed water flow rate, air flow rate, and the designs of the evaporator and condenser. A notable increase in productivity is linked to the expanded surface areas of these components. The study also explores the economic aspects of these systems, comparing costs in scenarios with and without the integration of phase change materials (PCMs), which are extensively used as packing media to improve thermal performance.