Spider mites are tiny arachnids that belong to the family Tetranychidae. They are often found on the undersides of leaves and can be identified by their small size, usually less than 1 millimeter, and their distinctive webbing. These pests feed on plant sap, which can lead to yellowing leaves and stunted growth. These mites thrive in warm, dry conditions and can reproduce rapidly, making them a common problem for gardeners and farmers. Effective control methods include introducing natural predators, such as ladybugs, or using insecticidal soaps and oils to manage their populations.