Google Adwords is the advertising system from Google.
If you have a website you may well already be 'paying per click' for relevant traffic. But Adwords has come a long way in the past few years, and with the world going mobile there are increasingly awesome solutions for small businesses to connect with customers.
Introduction
Google Adwords enables an individual or a business to access their target audience through Google Search, YouTube, or through partner channels. In other words, people 'search', your advert appears as an option in the Search results.
Source : https://www.plusyourbusiness.com/how-does-google-adwords-work/