Application Pool and Application Domain? What is the difference between the two.

1)Application pool is a grouping of URLs that is routed to one or more worker processes.

2)An application pool is a group of one or more URLs of different Web applications and Web sites. Any Web directory or virtual directory can be assigned to an application pool.
Every application within an application pool shares the same worker process executable, W3wp.exe, the worker process that services one application pool is separated from the worker
process that services another [Like starting MS Word and opening many word documents]. Each separate worker process provides a process boundary so that when an application is assigned to one application pool, problems in other application pools do not affect the application. This
ensures that if a worker process fails, it does not affect the applications running in other application pools. [i.e] for Eg., If word document is having issue it should not
logically affect your Excel Sheet isn’t it. application domain is a mechanism (similar to a process in an operating system) used to isolate executed software applications from one another so that they do not affect each other. [i.e] opening of MS WORD doesn’t affect MS EXCEL
you can open and close both the applications any time since there is no dependency between the applications. Each application domain has its own virtual address space which scopes the resources for the application domain using that address space.