Environments are where Massdriver bundles are deployed. Environments can be modeled by application stage (production, staging, development), by region (prod-usw, prod-eu), and even by your customers (cloud credentials are set per environment). Environments have parity of resources, but not scale. This allows environments to share the same architecture of infrastructure and applications, but have different configurations based on the intention of the environment. When you create a new environment, your architecture is automatically replicated and ready to deploy.
Environments, like deployments, can also be diffed. This allows you to quickly see the different configurations between environments.