What is Artificial Intelligence?

Most of us first get to experience about AI through Sci-Fi movies. You might have watched at least one AI movies from all time favorite AI movies such as Metropolis, Terminator, Blade Runner, Wall-E, Ex-Machine etc. But not like in the movies, AI in real life is not even closer to what we see in them even up to today. So where did it all start in real life? And how did it start?