A referenceless self-clocking (n,k) bar code word allows conveyance of
information without the need of any start and/or stop code pattern or
other reference; a code word pattern is repeated at least in part without
space therebetween according to a given n,k coding convention so that any
k pair of adjacent data code elements sensed by any sensing means
according to the n,k coding convention will consist of n units (e.g., bar
code modules), thus allowing the data code elements of the code word to
be decoded most accurately without any reference pattern. One application
of this coding is on round or cylindrical objects like coins, casino
chips and the like, and this coding is also well suited for linear or
other coding applications wanting to convey coded information without the
use of a start/stop code or reference pattern using n,k coding. This
coding may or mayn't include error control, for example, as disclosed
herein.