Chapter 7
- At a high level, asynchronous programming aims to avoid idle waiting for unavailable resources. This typically involves interacting with slow and unpredictable resources.
- A callback is a function that will be called at a given, later time. A future, on the other hand, is a more convenient abstraction that helps us keep track of requested resources and whether they are available. Futures are generally easier to use than callbacks.
- A reactive application should be responsive, elastic, resilient, and message-driven.