Jumping spiders have excellent eyesight, perhaps the best of any arthropod. This pantropical jumper (Plexippus paykulli) is making use of that capability as it stares down the photographer! Of course, the most important reason for those huge front eyes is to help the spider hunt prey. One of our larger jumping spiders, this species is native to Asia but has been transported to other continents. It is quite common in warm climates and, here in the U.S., is very frequently associated with manmade structures. From my own observations, I'd say it prefers concrete, brick and gravel.
This individual is a female. Her distinctive brown and white markings are so different from the black and white patterns on the males that they almost look like different species.