Offline analytics vs online analytics

An Offline Marketing Analytics are totally on speculation no real-time data. You don't pay for how many people are actually concentrating on your advertisement, when you try to propagate your message to mass. But you get all of them Online. You pay for people who really have visited your website and Digital marketing efforts helps to converting the visits to sales such as When you buy facebook likes, you are only paying for the number of people who have liked your page not the ones to whom your page is being advertised.