Explain the difference between uncharacteristic behaviour and inappropriate behavior?

Uncharacteristic behaviour is when someone acts unlike the way they usually act, say if I was shy and retiring and then one day I jumped on to a table and started dancing and singing, then that would be uncharacteristic behaviour. Whereas inappropriate behaviour is behaviour that is deemed unacceptable in those circumstances, say if i was in an exam and we had to not talk etc, then suddenly i leapt up and started shouting and screaming and ripping up exam papers, that would be inappropriate behaviour because it is 'against the rules' in that particular circumstance.