Notification Types

In this chapter, we will talk about all kinds of notifications. I'm sure you have heard about some of them:

Push Notifications - these are notifications sent to the device from some server. Best examples are new messages in social networks: when remote server finds out you have some incoming message, it will send a notification to you.
Local Notifications are scheduled and fired locally. It can be some tasks in your to-do list, some calendar events, etc.
NSNotificationCenter notifications. These are actually a very different type of notifications and used by your app only. This type of notifications is not visible by a user. Some object can send a notification, and all other objects will be able to receive it, and fire a custom action if needed.