A rubber band ball is a spherical object made by wrapping numerous rubber bands around a core, which can be anything from a small ball to a piece of paper. The process of creating a rubber band ball involves stretching and layering the bands, which allows them to grip each other and maintain the ball's shape. Rubber band balls can vary in size, from small, handheld versions to large, impressive creations. They are often used as stress-relief toys or desk decorations. The concept of a rubber band ball is popularized by the Rubber Band Ball Challenge, where participants compete to create the largest ball possible.