Three types of early portable timepieces are being distinguished:
Only the first two of these three types of timepieces are certain to have existed during the lifetime of Peter Henlein (approx. 1480 - 1542). However, since the first depiction of a neck watch dates to 1545 it is very likely that it has been created during his lifetime as well. Hence we refer to all three of these as 'Henlein-watches'.