For years, the internet has run on pay -per-click advertising. Advertisers buy ads and pay the publishers for every click. Click fraud, in which an individual or automated software program clicks on ads to drive phony impressions and clicks has exploded over the past decade to exploit this advertising model.
In fact, it has gotten worse as fraudsters have become more sophisticated. Today, they randonize IPs or device IPs to try to make the traffic look human.
They also use lot networks that drive fake impressions to specific. Sites for concrete time frames and hide barmery in the background, so that even though impression were counted, the bammers was never actually seen.