Human intelligence is the intellectual prowess of humans, which is marked by complex cognitive feats and high levels of motivation and self-awareness.
artificial intelligence :the theory and development of computer systems able to perform tasks normally requiring human intelligence, such as visual perception, speech recognition, decision-making, and translation between languages.
Human Intelligence is the inbuilt intelligence in human brain which deals with performing enormous number of tasks simultaneously whereas artificial intelligence is a Complex Model proposed for a limited number of tasks by human through Logic, rules, knowledge, inferences etc.. In precise, through AI, we attempt to simulate HI, but a long way to go to achieve it.
A large part of present-day human intelligence is already artificial. Language and notational systems are conventional and much of our need for memorization has been out-sourced to human artifacts such as books and hard drives. We've come a long way since Ardipithecus ramidus.