A game series is a collection of video games that share common characters, settings, or gameplay mechanics. These games are often released in a sequence, with each installment building on the previous ones. Popular examples include the Super Mario series and the Call of Duty franchise, which have both expanded their universes over time. Game series can vary in style, ranging from action-adventure to role-playing games. They often feature recurring themes and storylines, allowing players to immerse themselves in familiar worlds. Successful series may also lead to spin-offs, merchandise, and adaptations in other media, such as movies or television shows.