That may be an ok analogy, but magic isn’t real. Maybe a better analogy would be to speak or write in a language that you know certain people don’t natively understand, and using lots of slang and idioms that don’t translate easily. Someone could still run it through Google Translate or whatever, but they won’t get a great understanding of what you actually said. They’d have to actually learn the language and the sorts of slang and idioms used.