I am doing some objective-C / iOS development and have heard several references to the Actor pattern. In Big Nerd Ranch book, it says:
An actor object is used when you have a long running task and some code that needs to be executed after it completes. This kind of object is given the information it needs to perform the task and callbacks to execute when that task is done. The actor runs on its own thread without any further input and is destroyed when it is finished.
The actor here is used in conjunction with a network call. Is this how the Actor is primarily used? Is it mutually exclusive or complimentary to delegation? The Actor definition seems VERY broad and I am trying to get a better handle on what it means. Also, is it possible to have an Actor in a non-OO environment?