Display Environment Variables and their Values They are typically named in uppercase, with words joined with underscore ( _), e.g., JAVA_HOME.
COMPUTENAME, USERNAME: stores the computer and current user name.PATH: the most frequently-used environment variable, which stores a list of directories to search for executable programs.Environment variables are useful to store system-wide values, for examples, Environment variables are global system variables accessible by all the processes/users running under the Operating System (OS), such as Windows, macOS and Linux.
