Environment variables allow you to change an application's internal configuration without changing its source code. Let’s say you want to deploy the same application in development, testing and production environments. Then database related configs and some other internal configurations may change from one environment to another. If we can define these configurations as an environment variables we can easily set those without changing the source code of that application. When you deploy your application in WSO2 Integration Cloud, it lets you define environment variables via the UI. Whenever you change the values of environment variables, you just need to redeploy the application for the changes to take effect. Predefined environment variables Key Concepts - Environment Variables provides you some predefined set of environment variables which will be useful when deploying applications in WSO2 Integration Cloud. Sample on how to use environment variables U se