Google has a huge user base and hence it provides an authentication service for third party service to integrate with them so that people can sign in with Google in their services. Google also adopts OAuth 2 to provide this kind of Open ID connect service.This post will introduce how to integrate with sign in with Google functionality in your PHP website. Create a client app on GoogleThe first step you should follow is to create a Google app, you can follow the post here to create the project. Once the project is created, you will get a client id and client secret, these will be used late...