AdWords or Google AdWords is basically an advertising platform which allows advertisers to display their product or services on various online platforms or any application which is on playstore.
This particular way has evolved as one of the main stream for Google to earn revenue and in 2018 the total advertisement revenue generated by Google is about US$116.3 billion.
The methods or service offered by Google is pay per click(PPC) model which is actually the way the advertiser has to pay the number of times any person click on their advertisement.