Rule reminder
'Piacere' means 'nice to meet you' / 'pleased to meet you'. You can also say 'Piacere di conoscerti' (informal) or 'Piacere di conoscerLa' (formal). The response to 'Piacere' is also 'Piacere!'
Which of these phrases would you use only with a new acquaintance, NOT with an old friend?