Pull - This is when content is supplied to the viewer only when they want to be exposed to it. This strategy can include interactive features. A TV related "Pull" service typically allows viewers to decide if they want to access more in-depth content, often in an on-demand and interactive manner. "Push" presents the content to the viewer whether the viewer wishes to access it or not. Push is the opposite of "pull". https://en.wikipedia.org/wiki/Pull_technology