What do dermatologists do with a suspicious mole?

I've got a wierd-looking mole on my back that I'll probably have to have checked out. What will the doctor do to remove it if it turns out to be dangerous?What do dermatologists do with a suspicious mole?
i had one on my chin the doctor took a little blade and took a piece for testing then told me that is how they would remove it if dangerous it felt like when you cut your leg shaving wasn't too bad

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