▁establish ments ▁in ▁Pennsylvania <0x0A> </s> ▁A ▁b idd ing ▁system ▁in ▁contract ▁bridge ▁is ▁the ▁set ▁of ▁agre ements ▁and ▁understand ings ▁assigned ▁to ▁calls ▁and ▁sequences ▁of ▁calls ▁used ▁by ▁a ▁partners hip , ▁and ▁includes ▁a ▁full ▁description ▁of ▁the ▁meaning ▁of ▁each ▁treatment ▁and ▁convention . ▁The ▁purpose ▁of ▁b idd ing ▁is ▁for ▁each ▁partners hip ▁to ▁as certain ▁which ▁contract , ▁whether ▁made ▁or ▁defeated ▁and ▁whether ▁bid ▁by ▁them ▁or ▁by ▁their ▁oppon ents , ▁would ▁give ▁the ▁partners hip ▁their ▁best ▁scoring ▁result . ▁ ▁Each ▁b idd ing ▁system ▁as cri bes ▁a ▁meaning ▁to ▁every ▁possible ▁call ▁by ▁each ▁member ▁of ▁a ▁partners hip , ▁and ▁presents ▁a ▁cod ified ▁language ▁which ▁allows ▁the ▁players ▁to ▁exchange ▁information ▁about ▁their ▁card ▁hold ings . ▁The ▁voc ab ul ary ▁of ▁ ▁is ▁limited ▁to ▁ 3 8 ▁different ▁calls ▁- ▁ 3 5 ▁level / den om ination ▁b ids ▁plus ▁pass , ▁double ▁and ▁red ouble . ▁Any ▁bid ▁becomes ▁a ▁contract ▁if ▁followed ▁by ▁three ▁success ive ▁passes , ▁therefore ▁every ▁bridge ▁bid ▁is ▁a ▁potential ▁contract . ▁ ▁By ▁the ▁rules ▁of ▁the ▁game , ▁the ▁agreed ▁mean ings ▁of ▁all ▁calls ▁must ▁be ▁public ▁and ▁known ▁to ▁the ▁oppon ents . ▁In ▁normal ▁club ▁or ▁home ▁play , ▁the ▁oppon ents ▁are ▁entitled , ▁at ▁their ▁turn ▁to ▁make ▁a ▁call , ▁to ▁ask ▁the ▁partner ▁of ▁the ▁bid der ▁about ▁the ▁meaning ▁of ▁the ▁call . ▁ ▁In