Qaphela okokuba inkcazo nge-device njenge-input okanye i-output ixhokeke ekubeni iviwa njani na. Ii-Mouses kunye nee-keyboards zixhobo ezenza intshukumo ebonakalayo ye-input esetyenziswa ngumntu ukuza akhuphe i-output (isiphumo esilulwazi) ethi iguqulelwe kwii-signals ezinokuqondwa zii-understand. I-output eyenziwe zezi devices ibayi-input yekhompyutha. Ngokufanayo, ii-printers nee-monitors zikwazii-signals ze-input ezenziwa iyikhompyutha ukuba zibe zii-outputs. Ziyakuthi ke ngoko ziguqule ezi signals zibe yinto enokubonwa okanye enokufundwa ngabantu abazisebenzisayo. (Kumntu oyisebenzisayo oku kufunda nokubona amagama kukufumana i-input.)