Is an oral apology or a written apology better?

An oral apology is better because it shows that you care enough about the person to say sorry to their face.

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While I agree with the above.. I also feel that there is a level of severity to consider; a verbal apology, with honesty, is fine depending upon the offense. While a written apology should be reserved for offenses that involves several people or of grave concern to the person(s) offended.