The Google AdWords API allows apps to interact directly with the Google Ads platform, vastly increasing the efficiency of managing large or complex Google Ads accounts and campaigns. Some typical use cases include:
Automated account management
Ad management based on inventory
Bid management based on business data
With the AdWords API you can build software that manages accounts from the customer level down to the keyword level. The API can do almost everything the Google Ads UI does, but programmatically.
The types of companies that have benefited from the AdWords API include:
Search Engine Marketing (SEM) companies
Big brands managing a large number of accounts, with needs beyond what's possible within the Google Ads UI.
The API relies on SOAP and WSDL technologies to offer its services. You set up API access by obtaining a few required authentication credentials, creating some test accounts, and adding the authentication and account details to a configuration file for your client library. Authentication is via OAuth2.
To help you get started, they offer client libraries in Java, .NET, Python, PHP, Perl, and Ruby.