There are three main timelines on here:

🏠 Home - Posts from people you follow, plus posts featuring hashtags you follow

👥 Local - Public posts from people on your server

🌎 Federated - Public posts from people on any server

On the official Mastodon app, Local is known as "Community" and can be accessed by clicking the magnifying glass 🔍 and scrolling across to the Community tab.

There are no algorithms hiding or moving stuff. You see all the posts for each feed in chronological order.