Why are some answers highlighted in green?

I see some answers which are highlighted in green. What do they mean ?

The answers highlighted in green are the ones that have been accepted by the user who has asked the question. However, if you think that there’s some information missing from the accepted answer or you just want to give some input that you think is useful, you can post it in the comment section. Nevertheless, if you have enough karma to edit an answer, you may directly edit the answer.

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