There are four timelines on Mastodon:

HOME - Posts from people & hashtags you follow, in chronological order

EXPLORE - Trending posts, tags, links (on the official apps click the magnifying glass and leave search empty to see Explore)

LOCAL - All public posts from your server (on official apps click the magnifying glass 🔍 then scroll to Community tab). This works much better on small-medium size servers.

FEDERATED - All public posts your server can see. Not available on official apps.

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