The advertising trap

Digital advertising has taken over the world. But is it all based on smoke and mirrors? Ed Butler investigates what some claim is a massive collective deception - a trillion dollar marketing pitch that simply does not deliver value to any of those paying for it. Do online ads actually work, or could it be that some of the biggest names in global tech - from Google to Facebook - are founded on a false prospectus?

(Photo: Woman taking selfie. Credit: Getty Images)