Hi,
many coins have non-symmetrical edges, that is, there are two distinct classes of outcome of the minting process: either the coin is put between the dies in the one direction, or in the other direction, so an inscription on the edge could be readable with face up, or with number up - also, the text could start at any position of the edge, giving infinitely many "variants".
Some time ago, a lot of coins had the possibility to enter your coins in either of two lines, saying "Type A" and "Type B", but I think most of the distinctions in Numista have been deleted since (has there really been made any decision?)
discussion was for example here:
https://en.numista.com/forum/topic6167.html
There are still some coins with two lines for each year, like this
https://en.numista.com/catalogue/pieces34905.html
Should we delete this? Or should it stay, because people are happy with it?
I personally am against this distinction, as it (first) is a really random outcome of the minting process which has little meaning, and (second) it makes swapping more difficult for those who don't care about which edge type their coins have.