The former, the Archival board is used to store "old stuff". Some of the purposes are cited in this old thread that asked the same question: How does the archival board work? , including, but not limited to:
- Store content of threads which are no longer needed (i.e. someone sold something and do not wish to keep the thread visible in the Marketplace, or long time finished campaigns).
- Create test threads.
- Act as a repository for obsolete boards/childboards (i.e. Removing Multibit section.
There’s this to go by:
The later, Archive external sites, are used for references in cases such as describes in this thread, as they conform a snapshot of a given page at a certain point in time. I often use them to retrieve statistical information (i.e. Archived Bitcointalk Index pages (https://bitcointalk.org/index.php) to retrieve the number of posts at a given point in time), and often they allow you to view historical information that is no longer available, such as this:
Assuming stats are true to reality (*), since the chart shows the data from a non-logged account (see https://web.archive.org/web/20140420114108/https://bitcointalk.org/index.php?action=profile;u=3;sa=statPanel), the data shown should be in UTC. I’d say sleep times are from 7 UTC to 12 UTC, which for an IT intensive person could fall in the range of 2AM-7AM roughly (give or take an hour). Mapping 7 UTC to 2 AM would place the physical location to be in the UTC-5 range, which is most likely to be USA or Canada (see https://24timezones.com/timezone-map).
(*) I assume the stats are true, but they could have been altered (backoffice, on the Bitcointalk DB) at some point to throw people off course. The earliest snapshot I’ve found is from April 2014, over three years after the last connection from the account).
Anyhow, pure speculation ...