Process.env
process.env.HELLO
Code Cat
process.env.HELLO"NODE_ENV is an environment variable made popular by the
express web server framework. When a node application is run,
it can check the value of the environment variable and do different
things based on the value.
NODE_ENV specifically is used (by convention) to state whether
a particular environment is a production or a development environment.
A common use-case is running additional debugging or logging code
if running in a development environment."