Forgiving

What is forgiving according to you? Is it possible for you to forgive? One of the many definitions for 'forgive' in the dictionary is "to cease the feeling of resentment". Is this always possible? And does forgiving mean that you also give up your judgement about a person?

Is it always good to forgive anybody for anything or do you make a decision on a case-by-case basis, some people being more worthy of being forgiven than yet others? And continuing this train of thought, is forgiving yourself usually harder or easier for you than forgiving others?

As per most (or may be all) religions forgiving is a virtue and God always forgives. Going by the definition of God, nothing can adversely affect God so why would He/She/It care either way? Isn't forgiving only applicable when someone is affected in some way? Does forgiving also mean that you don't punish the other person? In that case, why is it that religion talks both about an all-forgiving God and at the same time, going to hell for one's sins?

I would love to hear your take on this subject!