Typically one of development, staging, or production, each environment may exhibit different behavior depending on configuration and template logic. For example, in a production environment you might minify and fingerprint CSS, but that probably doesn’t make sense in a development environment.
When running the built-in development server with the hugo server command, the environment is set to development. When building your site with the hugo command, the environment is set to production. To override the environment value, use the --environment command line flag or the HUGO_ENVIRONMENT environment variable.
To determine the current environment within a template, use the [hugo.Environment] function.