those clowns at TTN are always yapping about them. I know what concentrated strikes can mean to participants, but a barrier?
It's a type of option, where a barrier level is set that will "activate" or "deactivate" the option, so to speak. Google it - should find plenty of info.
TTN is quoting Bloomberg or Thomson regarding FX touch barriers and less common exotics. The EURJPY 165.00 touch pays the buyer if 165.00 is touched at any time until expiration. They're priced on touch-probability in fixed-odds. Touch-probability is 2x expiry-prob and is solved via BSM, GaKo, BjSt, bi/trinomial, etc. A 70/100 payout reflects a 70% touch probability. $70 pays $100 if 165.00 is touched. The no-touch is the reciprocal-market; it pays 30/100 if 165.00 is not touched.