Namespace

Symfony\Component\HttpKernel

Client Client simulates a browser and makes requests to a Kernel object.
HttpKernel HttpKernel notifies events to convert a Request object to a Response one.
Kernel The Kernel is the heart of the Symfony system.
KernelEvents Contains all events thrown in the HttpKernel component

Interfaces

HttpKernelInterface HttpKernelInterface handles a Request to convert it to a Response.
KernelInterface The Kernel is the heart of the Symfony system.