A core design principle in software development is the separation of concerns. Each piece of information that affects the operation of the system is separated into a distinct section. In Drupal 7, a notable violator of that principle was hook_menu. It controlled routing, how a URI was mapped to the section of code that would handle the request, menu links, and local tasks, all using a specialized array with 23 different attributes. In Drupal 8 routing, menus and related items have all been separated out into their own components and configuration.
Routing and menus
Basic routing
A route is a way for Drupal to determine which system should be responsible for returning content to a request. For example, when it receives a request...
