An Environment Variable has a name and value. These variables are used to adapt each application's behavior to the environment it is running in. The information stored in the Environment Variable can be used by any one or multiple applications.An environment variable can have any information about the system as its value such as language that has to be used, the data in the file system, the default program that has to be used, or even system local settings. Environment Variables are very handy for sharing configuration settings among multiple Linux applications and processes.