used to give an affirmative response

‘Do you understand?’ ‘Yes.’

used as a response to someone addressing one or trying to attract one's attention

‘Oh, Mr Lawrence.’ ‘Yes?’

used to question a remark

‘It should be easy to check.’ ‘Oh yes? How?’

encouraging someone to continue speaking

‘When you bought those photographs …’ ‘Yes?’

expressing great pleasure or excitement

plenty to eat, including hot hamburger sandwiches (yes!)

expressing irritation or impatience

‘Is the pain still there?’ ‘Yes, yes, damn you, the pain is always there’

an affirmative answer or decision, especially in voting

answering with assured and ardent yeses