Digital out of home (DOOH) advertising using screens and billboards has grown significantly in major cities around the world. DOOH advertising is more effective than traditional static posters because it can include animation and video. DOOH advertising also allows audiences to interact through technologies like QR codes and image recognition on their mobile devices. Research has shown that DOOH campaigns in locations like airports can be very effective for certain products since people have more time to browse in those environments. Neuroscience research also indicates that campaigns which require more cognitive effort from the audience, such as puzzles or stories, are more likely to be remembered by consumers in the long term.