Advertising has been on the Internet since it was first commercialised. Banner ads used to be commonplace on websites to draw consumers into clicking and buying something they may want.
Advertisers have become more complex as they have to show their customers the results of their labour to get paid. How many impresions (how many people have seen the ad) and clicks (the number of people who clicked on the ad) are all important metrics.
Advertisers have also had to cope with a small but growing sector, the ad blocker.
An ad blocker is a program that intercepts the ads before they appear on the browser, so could be replaced by a blank image or removed entirely.
The evolution came when ad companies started introducing software that detects a blocked ad and prevents the page from being shown if its blocked.
Ad blocking has evolved further with the advent of Pi-Hole, a piece of software that runs on a Raspberry Pi (or similar hardware) that blocks the names of the ad companies servers so the web browser loads the page quicker.
Advertisers now have a choice to move adverts to the website the pages are hosted on (like they used to be) or face obliteration as more people want their pages to load quicker and purchase a pi-hole device.