It is very easy to differentiate human from the computer, except for if a time comes as technology is advancing that there might be creatures with half human and half computer. First of all, both human and computer depends on electricity but in a different capacity, as a human can still function without electricity, but computer depends fully on electricity to function. But as the computer relies on electricity, human relies on food for survival and to function effectively.
Human has been a long time before the invention computer, though there is rapid advancement in the performance of the computer. Though these two entities have memories for storage, humans are good at reasoning and imagination, while computers are exemplary fast at logic and computation. The computer also has a better and longer sustaining memory ability than human. Both can also multitask, but the computer can do it better and faster simultaneously. The human can get easily worn out or tired, while a computer can work for days, neglecting some unexpected external factors.