Stigma is the reaction that the public have when it ties down to those who struggle with mental illnesses. There are two different types of stigma, self-stigma, and public-stigma. Self-stigma is what happens when people with mental illnesses turn against themselves, while public-stigma, as stated before, is how the population in general views mental illnesses.
I hope this gives you a general idea. Let me know if it doesn't fully answer your question.
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