Google Ads, aka Google Adwords, is a platform that helps the advertiser to display the ads to the relevant users based on the appropriate keywords and Ad copy they create with a competitive bid amount. They have two types of inventory sources.

• Google Search Network
• Google Display Network

In Search Network Text ads, shopping ads will display on the Google Search Page and search partner sites where a Google Display Network has nothing to do with Google Search page; instead, they have millions of Websites and Apps integrated with their network. In GDN websites and Apps, Google Ads serve the Display and Video Ads. 

Bluntly, Google ads are a platform that helps to serve them relevant advertisements to the user and helps to drive performance for the advertiser. where GDN is a Network of millions of websites and Apps with inventory to sell when a demand with reasonable price comes from Google Ads or any advertisers of Google Marketing Platforms