The AdWords advertising network was created by Google in 2000. It has grown considerably, which is not without raising certain criticisms and for a good reason: Commercial links have gradually invaded search results (SERP), to the point of masking "natural" results on certain queries.
Advertisers can always pay when a user clicks on an ad through a high-quality auction system. The more relevant the ad is to the user, the lower the cost per click, and the higher the ad. This is to encourage advertisers to provide information relevant to a user's request.
"AdWords" comes from "Ad" for advertising and "words". In 2018, Google Adwords changed its name to simply Google Ads.