What is firebase in android?

FireBase is a BaaS That allow you to build an online application without having to develop/program a server back-end.    

It's an online platform that give free services which can help you to build your app easily.

it is a programming environment that contains many tools and APIs that will help you build applications for Android and ios systems in addition to the web more easily and quickly.

You will find that it has many utilities in the creation and conversion of applications between different platforms and environments in addition to storage, hosting and messaging services and reports of problems and errors and other services that will save you time and effort in the creation of various applications.

Firebase is a cloud api provided by google. It is a backend as a service model. It privides several services like real time database, analytics etc. With firebase developers don’t need to manage or maintain any kind of server. All server side is managed by google’s firebase.

FireBase is Google complete backend solution.This is not specific to android only, it can be used with all major platforms like android, ios and web etc. for android it will provide same features as it is giving to all other platforms.it has Authentication (with major platforms like google , facebook etc), it has database (document database), it as storage and many more

Database System , backend for application that can save realtime data.

firebase is server. it provide real time database,push notification ,user athentication

Firebase is a back end for android app development when link to android studio.

Firebase works like your backend for the mobile application. As a mobile developer you no need to worry about Web service or perfomance of server or anything related to server side. 

Using firebase you can 

Real time database,

Push notification,

Firebase Analytics,

Firebase Authentication, 

and many more features. 

Firebase is sum of all these answers.

firebase is a services supported by google to store your data or push notification or make an authuntcation  for usere emails or onther service you want .