Allon kwamfuta yana nufin na'urar nunin lantarki da ake amfani da ita wajen gabatar da kayan aiki daga kwamfuta. Ana kuma kiransa Monitor ko nunin allo, kuma ita ce babbar hanyar sadarwa tsakanin mai amfani da kwamfuta. Allon kwamfuta yana nuna rubutu, zane-zane, da sauran hotuna da cibiyar sarrafa kwamfuta ta tsakiya (CPU) da sauran kayan aikin kwamfuta suka samar. Allon na iya amfani da fasahohi iri-iri, kamar nunin kristal na ruwa (LCDs), diodes masu haskaka haske (LEDs), ko bututun ray na cathode (CRTs), don nuna bayanai.