An independent film producer set up an account with a service that captures viewer information such as email addresses, phone numbers, geographic location, and other demographic information when viewers click on a film's website to watch a trailer. This information is being used to push marketing messages and information about the film to its potential audience as it rolls out to various area theaters around the country encouraging people to see the show and bring along a friend. This example of marketing illustrates which unique attribute associated specifically with digital marketing?