Named editions sold openly, so a household, a class or a puzzle club
can all work the same register at once, compare where they have got
to, and argue about it. Most books on this site are sold to one buyer
only; these are the ones made to be shared.
Everyone in the group buys their own copy, on their own account, and
gets the PDF and their own saved progress.
Because more than one person owns these, an answer to one can
circulate. If you would rather hold the only copy in existence, take
the short book or
the long one instead.
