The purpose of this paper is to explore the meanings of modding from the perspectives of game modders. There are three analytical categories used in the research: 1. modders' personal motivations and pleasure-seeking needs, 2. their relations to other players in the game communities and, 3. their relations to the game industry. Results of qualitative interviews indicate that, modders make mods to gain pleasures, to construct and maintain social relations and to get money and knowledge. Game community is the site where modders can express themselves, gain the sense of accomplishments and share collective knowledge. Despite there is possible copyright violation by game modders, the game industry still works to accommodate with the modding culture in order to further commodify gameplay and maximize profits.