▁The ▁engineer ▁should ▁focus ▁on ▁developing ▁a ▁design ▁that ▁optim izes ▁the ▁constraints ▁but ▁ens ures ▁a ▁work able ▁and ▁reliable ▁product . ▁ ▁The ▁architect ▁is ▁primarily ▁concerned ▁with ▁the ▁comfort ▁and ▁us ability ▁of ▁the ▁product ; ▁the ▁engineer ▁is ▁primarily ▁concerned ▁with ▁the ▁produ ci b ility ▁and ▁utility ▁of ▁the ▁product . ▁▁ ▁The ▁provision ▁of ▁needed ▁services ▁to ▁the ▁user ▁is ▁the ▁true ▁function ▁of ▁an ▁engine ered ▁system . ▁ ▁However , ▁as ▁systems ▁become ▁ever ▁larger ▁and ▁more ▁complex , ▁and ▁as ▁their ▁ ▁em ph ases ▁move ▁away ▁from ▁simple ▁hardware ▁components , ▁the ▁narrow ▁application ▁of ▁traditional ▁hardware ▁development ▁principles ▁is ▁found ▁to ▁be ▁ins u fficient — the ▁application ▁of ▁the ▁more ▁general ▁principles ▁of ▁hardware ▁architecture ▁to ▁the ▁design ▁of ▁( sub ) ▁systems ▁is ▁seen ▁to ▁be ▁needed . ▁ ▁A ▁Hard ware ▁architecture ▁is ▁also ▁a ▁simplified ▁model ▁of ▁the ▁finished ▁end ▁product — its ▁primary ▁function ▁is ▁to ▁define ▁the ▁hardware ▁components ▁and ▁their ▁relationships ▁to ▁each ▁other ▁so ▁that ▁the ▁whole ▁can ▁be ▁seen ▁to ▁be ▁a ▁consistent , ▁complete , ▁and ▁correct ▁representation ▁of ▁what ▁the ▁user ▁had ▁in ▁mind — es pecially ▁for ▁the ▁computer – human ▁interface . ▁ ▁It ▁is ▁also ▁used ▁to ▁ensure ▁that ▁the ▁components ▁fit ▁together ▁and ▁relate ▁in ▁the ▁desired ▁way . ▁ ▁It ▁is ▁necessary ▁to ▁distinguish ▁between ▁the ▁architecture ▁of ▁the ▁user ' s ▁world ▁and ▁the ▁engine ered ▁hardware ▁architecture . ▁ ▁The ▁former ▁represents ▁and ▁addresses