The user’s newsfeed is built by his home node in the background. The user instructs the home node to subscribe to the nodes he wants to read. The home node in the background fetches the content from these nodes, receives notifications about updates and other information it needs and builds the newsfeed. The user may read it at any moment using a Moera client.
There are many possible algorithms of newsfeed composition. From the simplest - all posts in the reverse chronological order - to very complex, with grouping, filtering, statistical analysis and AI. The newsfeed content is not limited to posts - any other news, events, important pieces of informations may be added to the feed. The newsfeed composer may be integrated into the node software, or node owner may decide to use some third-party service (paying by his privacy). The choice is in the user’s hands.
It is recommended not to change the newsfeed after it was read. The new posts should be added to the end (or the beginning) of the feed and this “active part” of the feed may change in the process of composition. But after it was seen by the user, it is recommended to lock it, so the user may be able to find the posts he just have seen. It also simplifies the client and makes caching possible.
In particular, this means that the posts appear in the newsfeed not in the order of publication, but in the order they have been received by the newsfeed composer. Some posts may appear in the feed several times - for example, if the algorithm is instructed to pop up the most popular posts. Unsubscribing means you will not receive new posts from this source anymore, but the posts you received earlier do not disappear (while it is possible to remove them explicitly).
Since the posts may be edited or removed by the author, the notifications the subscriber receives include not only the posts, but also editing and removal events (and maybe even more - like change in the number of reactions or comments). Note that the subscriber may decide not to include these changes into his copy of the post, to keep all revisions of it or to preserve the post that the author wants to be deleted. There is no way to avoid this - even in centralized systems anybody can copy-paste a post or make a screenshot.
(A node may add a delay between receiving a post from the node owner and publishing it and sending notifications. This may give a chance to the author to think again and make changes not visible to others.)
A node may decide to send notifications about old posts that changed their visibility from private to public and now available to be read by subscribers.
Simplified nodes may not support notifications. In this case subscribers need to poll such nodes periodically to get the updates. But polling may also be used intentionally - to preserve privacy. As we already said, public posts may be read without authentication, so the fact you’re subscriber will not be disclosed.
Notifications box is a button, usually in the top-right corner of the screen, where you see quick notifications about the most important events - reactions to your posts, replies to your comments or anything else you want to see and respond quickly.
In Moera the content of the notification box is built as one more newsfeed, but for different set of events.
Worth noting that you may have any number of different newsfeeds for different purposes and they may be shown on separate pages, in sidebars, dropdown menus - how the client wants to present them. Read whatever you want using an interface of your choice - that’s the power of Moera.