These are patterns for the latin language mainly in modern spelling (u when u is needed and v when v is needed); medieval spelling with the ligatures \ae and \oe and the (uncial) lowercase 'v' written as a 'u' is also supported; apparently there is no conflict between the patterns of modern Latin and those of medieval Latin. The patterns support the restricted character set of the OT1-encoding (obviously without the ligature characters), as well as T1-encoded usage.