Theming in a Design System refers to the ability to customize the visual appearance of a component library or UI library to align with a specific brand or interface. It is an essential aspect of Design Systems as it enables consistent and cohesive visual experiences across various products or platforms.

Theming allows teams to apply a unique look and feel to their interfaces while maintaining Design System standards. By leveraging Theming capabilities, teams can create visually engaging experiences that reflect the desired brand identity, enhancing overall user satisfaction and ensuring a harmonious user experience.