Instead of redistributing an entire 10GB game file (which is illegal), patchers allow creators to distribute a tiny 2MB patch file that contains only the differences between the original game and the modded version.
If you’ve been in the Nintendo Switch modding scene for more than five minutes, you’ve probably heard the term "ROM Patcher." It sounds technical, slightly intimidating, and—depending on who you ask—a little bit shady.
If you have a launch-model Switch (or a compatible modchip) and a legal copy of a game, patching opens up a universe of content you never knew existed.
Disclaimer: This post is for educational purposes only. Modifying your Nintendo Switch violates its Terms of Service, and online bans are permanent. Patch responsibly.