henrywright Not exactly, if I understood you correctly.
Newest refers to the start date of the topic. So some of my bug reports, since they were started yesterday, would show a few places down when sorting by newest.
Recent refers to the date/time of the most recent post on each topic. So since I just replied, this topic would show very close to, if not at, the top.
Replies refers to the amount of posts on each topic. Currently, if you were to sort by Replies, the word association game would be at the top, since it has the most posts.
Oldest is just like Newest, it just reverses the sorting to show the first topics ever created at the top. So if you sorted by Oldest, "Welcome to the Flarum Development Forum" would show first since it was the first topic ever created on this forum.
I hope this was a bit more clear.