ep is od ic " ▁share ware ▁model ▁that ▁became ▁the ▁most ▁popular ▁in cent ive ▁for ▁bu ying ▁a ▁game . ▁While ▁the ▁share ware ▁game ▁would ▁be ▁a ▁truly ▁complete ▁game , ▁there ▁would ▁be ▁additional ▁" ep is odes " ▁of ▁the ▁game ▁that ▁were ▁not ▁share ware , ▁and ▁could ▁only ▁be ▁leg ally ▁obtained ▁by ▁pay ing ▁for ▁the ▁share ware ▁episode . ▁In ▁some ▁cases ▁these ▁episodes ▁were ▁neat ly ▁integrated ▁and ▁would ▁feel ▁like ▁a ▁longer ▁version ▁of ▁the ▁game , ▁and ▁in ▁other ▁cases ▁the ▁later ▁episodes ▁would ▁be ▁stand - alone ▁games . ▁Sometimes ▁the ▁additional ▁content ▁was ▁completely ▁integrated ▁with ▁the ▁un register ed ▁game , ▁such ▁as ▁in ▁Amb ros ia ' s ▁Es cape ▁Vel ocity ▁series , ▁in ▁which ▁a ▁character ▁representing ▁the ▁developer ' s ▁pet ▁par rot , ▁equ ipped ▁with ▁an ▁und efe atable ▁ship , ▁would ▁period ically ▁har ass ▁and ▁destroy ▁the ▁player ▁after ▁they ▁reached ▁a ▁certain ▁level ▁representing ▁the ▁end ▁of ▁the ▁trial ▁period . ▁ ▁R acks ▁of ▁games ▁on ▁single ▁ 5   1 / 4   inch ▁and ▁later ▁ 3 . 5   inch ▁flo ppy ▁dis ks ▁were ▁common ▁in ▁ret ail ▁stores . ▁However , ▁computer ▁shows ▁and ▁bullet in ▁board ▁systems ▁( B BS ) ▁such ▁as ▁Software ▁Cre ations ▁B BS ▁were ▁the ▁primary ▁distrib utors ▁of ▁low - cost ▁software . ▁Free ▁software ▁from ▁a ▁B BS ▁was ▁the ▁mot ive ▁force ▁for ▁consum