This article targets new developers and developers which never had the chance working with multi versioned websites before. If this fit's you: Read it. Staging is a good tool in your belt you won't regret to know. [...] You, your co-developers, authors and whatnot using [staging] to prepare and test stuff which is to be released into production. In short: you do not perform open-heart surgery by coding directly on the production website.

He talks about the "stages" part of the "multi-stage" structure, mentioning the separation of purpose they provide and an example of a three level configuration (dev, staging, production). An optional fourth level can be added as well for testing purposes. There are some downsides to this approach, though: data synchronization, code deployment delay and complexity. There's also a mention of gitflow and how it could help make this environment easier to set up for your applications.