|(humour)||backward combatability - /bak'w*d k*m-bat'*-bil'*-tee/ (Play on "backward compatibility") A property of hardware or software revisions
in which previous protocols, formats, layouts, etc. are
irrevocably discarded in favour of "new and improved"
protocols, formats and layouts, leaving the previous ones not
merely deprecated but actively defeated. (Too often, the old
and new versions cannot definitively be distinguished, such
that lingering instances of the previous ones yield crashes or
other infelicitous effects, as opposed to a simple "version
mismatch" message.) A backward compatible change, on the
other hand, allows old versions to coexist without crashes or
error messages, but too many major changes incorporating
elaborate backward compatibility processing can lead to
extreme software bloat.|
See also flag day.