Wet waste primarily consists of organic materials, such as food scraps, vegetable peels, and other biodegradable items that decompose easily. Dry waste, on the other hand, includes non-biodegradable materials such as plastics, metals, glass, and paper. The key difference lies in their decomposition properties wet waste can break down and return nutrients to the soil, while dry waste can persist in the environment for decades, causing pollution and landfill overflow.