“Lemmy uses a voting system to sort post listings. - - You can upvote posts that you like so that more users will see them. Or downvote posts so that they are less likely to be seen. Each post receives a score which is the number of upvotes minus number of downvotes.
Active (default): Calculates a rank based on the score and time of the latest comment, with decay over time
Hot: Like active, but uses time when the post was published
New: Shows most recent posts first
Old: Shows oldest posts first
Most Comments: Shows posts with highest number of comments first
New Comments: Bumps posts to the top when they receive a new reply analogous to the sorting of traditional forums
Top Day: Highest scoring posts during the last 24 hours
Top Week: Highest scoring posts during the last 7 days
Top Month: Highest scoring posts during the last 30 days
Top Year: Highest scoring posts during the last 12 months
Top All Time: Highest scoring posts during all time”
Hot sounds a lot like what Reddit uses. They use some secret algorithm where each upvote is like a balloon that lifts the post up and as the post ages, more and more weights are added to it over time so that it sinks down and gives more space for newer posts.
Reading the documentation can be a bit boring, but you can always use Bing to summarize the main points and even ask specific questions about the text.