Rubber ducks are often yellow because this color evokes fun, cuteness, and brightness, which is especially appealing to children. Rubber ducks were originally designed as bath toys for children, and the bright yellow color easily attracts attention and creates a clean, fresh feeling when combined with a water environment. In addition, yellow also creates a good contrast with water and other items in the bathroom, making it easy to see and find. Although real ducks are brown, green, or gray to match their natural habitat, the goal of rubber ducks is not to look real, but to be more prominent and friendly to children and users.