Oh, as far as forgiving other people in the sense of openly telling them you forgive them....well, that's only useful if they are genuinely contrite and already desirous of forgiveness....as can sometimes happen. In that case, it's very beneficial to both you and them to tell them they are forgiven. Otherwise, you're definitely better off to keep your forgiveness quietly to yourself! It won't be apreciated if it isn't wanted. ;-) And in that case, it's you whom the process of giving forgiveness benefits, not the other person. It's like shedding a heavy load.

And then there's the challenge of forgiving yourself. For many people that might be the toughest one of all.