Google Search Ads is part of google ads (adwords) paid advertising platform that falls under a marketing channel known as pay per click (PPC), where you (the advertiser) pays per click or per impression (CPM) on an ad.
It is not secret that, now days, the powerfull and more focused your paid campaigns are, the more clicks you generate - leading to a greater probability of obtaining new customers. This is why Google Search Ads has become increasingly popular among businesses across all industries.
Your ads is show with Google search results and on other search sites when user's search keywords are relevant to the search.
Google search sites: Ads can appear above or below search results on Google Search. They will appear beside, above, or below search results on Google Play, Google Shopping, Google Images, and Google Maps - including the Maps app.
Google search partners: Ads might appear with search results on websites of Google search partners or as a part of a related search or link unit. For text ads, search partners include many non-Google websites, also as Google Video and other Google sites. Product Shopping ads can appear on search partner sites that display and link to products purchasable.