▁exist , ▁such ▁as ▁" one - hand ed ▁D vor ak " ▁and ▁" Left ▁hand ▁Ng ai h ". ▁Switch ing ▁the ▁keyboard ▁layout ▁is ▁often ▁required . ▁It ▁is ▁hence ▁incon ven ient ▁for ▁others ▁to ▁use ▁the ▁same ▁computer . ▁ ▁See ▁also ▁▁ ▁Ch ord ed ▁keyboard ▁ ▁Q W ER TY ▁ ▁Touch ▁typing ▁ ▁Human ▁mult it ask ing ▁ ▁D vor ak ▁Sim pl ified ▁Key board ▁ ▁References ▁▁ ▁Category : Typ ing <0x0A> </s> ▁A ▁da is ▁( ▁or ▁, ▁American ▁English ▁also ▁ ▁but ▁sometimes ▁considered ▁non standard ) ▁is ▁a ▁raised ▁platform ▁at ▁the ▁front ▁of ▁a ▁room ▁or ▁hall , ▁usually ▁for ▁one ▁or ▁more ▁speak ers ▁or ▁hon ored ▁guests . ▁▁ ▁Histor ically , ▁the ▁da is ▁was ▁a ▁part ▁of ▁the ▁floor ▁at ▁the ▁end ▁of ▁a ▁medieval ▁hall , ▁raised ▁a ▁step ▁above ▁the ▁rest ▁of ▁the ▁room . ▁On ▁this , ▁the ▁master ▁of ▁the ▁household ▁or ▁assembly ▁( e . g . ▁the ▁lord ▁of ▁the ▁man or ) ▁d ined ▁with ▁his ▁senior ▁associ ates ▁and ▁friends ▁at ▁the ▁high ▁table , ▁while ▁the ▁other ▁guests ▁occupied ▁the ▁lower ▁area ▁of ▁the ▁room . ▁In ▁medieval ▁h alls ▁there ▁was ▁generally ▁a ▁deep ▁re cess ed ▁bay ▁window ▁at ▁one ▁or ▁both ▁ends ▁of ▁the ▁da is , ▁which ▁provided ▁ret irement ▁or ▁greater ▁priv acy ▁than ▁the ▁open ▁hall . ▁The ▁da is ▁area ▁often ▁had ▁its ▁own ▁door way ▁for ▁ad