Drupal has the ability to manage multiple websites at once from a single code base.
This can lead to huge savings in maintenance and simplification of all development flows, and is especially useful for organizations that need to maintain a large number of web pages.
Unify code and simplify deployments
You can create several websites in Drupal that share the same functionalities but different configurations and databases, so that improvements and updates are made only once for all of them while retaining the customization of each one.
This is incredibly useful for organizations that need to maintain a lot of similar but not identical web pages. For example, a company with subsidiaries in several geographical areas, an organization that divides its online presence into minisites according to its target audience or a franchise system that needs a site for each franchisee without having to duplicate efforts.