Request

Information about incoming traffic is encapsulated in a request. Craft inspects the request, figures out how to route it, and assembles a response that is sent back to the client.

Not every HTTP request that arrives at your server is necessarily handled by Craft, though! Typically, files in your web root are automatically accessible without Craft—and Craft can generate URLs to resources that it may not be involved with serving (like an asset).

Internally, Craft also handles CLI actions as “requests.”