Poncelet porism is one of most beautiful and most important results of 19th century projective geometry: it states that existence of one closed polygonal line inscribed in a given conic and circumscribed about another one implies the existence of an infinite family of such polygons.
In the talk, classical results connected with Poncelet theorem will be overviewed as well as new ones connected with elliptical billiards and their higher-dimensional generalizations.