Jumpers don't make webs to catch prey; they stalk their subjects and nab them in a spectacular deadly leap. Such is their jumping ability that a six-foot tall person would have to be able to jump over the equivalent of a large building to match the leaps of a jumping spider. They also have the ability to process and temporarily store locational data. Thus, a spider can spot a potential victim, move out of sight and stalk while hidden behind obstructions, then spring with deadly accuracy from a new position without having eyeballed the soon to be dead prey since the initial visual contact.
Jumping spiders are charismatic, and many people who are died in the wool arachnophobes even find them "cute". It's as if the spiders watch you - they do!- and react to your movements. They often wave their forelegs about as if flashing semaphore signals. The spiders will cock their heads and seem to gaze curiously at you, and do not display much fear.
In the above video, the spider makes a wild leap for my camera lens, misses, and self-rescues via the safety line that he had attached to the leaf prior to the launch. Watch closely at the end and you'll see him rapidly climbing the line back to the leaf.
My cohorts thought the spider disliked me, and was attacking. And it's a darn good thing these jumping spiders aren't the size of Woodchucks! Otherwise, the video above would have looked very different. You'd have seen a large furry blob fly forward and block the camera view like an eclipse, hear me screaming crazily and rapid blurred images of spider legs and foliage whirring around as we tussled, the wild roars of my companions as they raced away in horror, followed by a grim stillness.
But they are not big and we have nothing to fear. This was cool, though. I think that the spider, with its incredible vision, probably saw its own reflection in the lens of my camera. Thinking its image to be that of possible prey, it stalked my camera and when the time was right, leapt. You can see it walk across the lens at the end.
Pretty cool stuff.