Firebase is a Backend-as-a-Service that helps kickstart your app and web development. It offers NoSQL databases, cloud functions, remote configuration, user authentication and analytics, error and crash logging, and more.
For mobile development, it also provides a handy tool to integrate push notifications into your application.
Why do we adopt this technology?
Firebase is offering a broad collection of services, many free of charge. While advanced features may sometimes be lacking, it's a solid base to start from.