Does vBulletin distinguish between "not-Read" and "New" threads?

[cpv204]

Does vBulletin distinguish between "not-Read" and "New" threads?

When I return to a site I've visited before, some threads have a yellow envelope icon next to them, indicating they have new posts since I last visited.

At this time I may choose to read only one or two of these threads.

When I come back the next day, these threads will have the blue No New Posts icon next to them if there haven't been any new posts, even the ones I didn't read.

Is there an indicator that tells me what threads I have or haven't read, as opposed to which threads have new posts since my last visit?

[JamesUS]

Unfortunately not - storing a read/unread check for each thread for each user would require a huge amount of disk space. For example, 5,000 users and 10,000 threads would take 50,000,000 rows in the database which would take lots of disk space and cause a huge performance hit.