Mods alter or add to the game they're created for, so you must have that game in your Steam library to utilize them. Do I need to own the game that the mod is made for? If a game doesn't support mods, you can tell the developers you'd like to see that feature by starting up a discussion on the game's Community Hub. You can also find mods related to a game by checking for the 'Community-made Mods' section on its store page.

Many games support mods through the Steam Workshop, where you can easily browse for new content and have it automatically appear in your game. You may just stumble across the next big thing and help it grow. Counter-Strike, Dota 2, and Team Fortress all began their life as mods. Some mods can even grow into full stand-alone commercial products. Supporting mods means supporting their authors, and encouraging them to update their existing mods and make more and better mods in the future. Other mods may add expansive community-created content equaling hours of new gameplay and storyline, or even an entirely new game built from the ground up. Many mods are free and range in scope from smaller changes here or there to entirely new items, characters, maps, or missions. Steam makes it easy to find and try these mods for any game in your library that supports modding. Whether it's adding new graphical features, crafting new items, or creating new stories, mods can breathe new life into games of all types. Fans, hobbyists, and aspiring game developers from around the world can add to or modify their favorite games by creating 'mods'. Your favorite games don't need to end just because you've finished them.

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