This is a Zebra Jumper (Salticus scenicus), or zebra spider. It is a type of jumping spider that hunts on foot for prey rather than spinning a web.
This is a Zebra Jumper eating an Orange mint moth (Pyrausta orphisalis) on my back fence, near the edge of a Marbled cellar spider's web.
Moments later, the Marbled cellar spider (Holocnemus pluchei) wrested the moth from the zebra jumper. (Is that the arachnid equivalent of mean kids taking your lunch money? )
Here's another little zebra jumper on the back wall of my house who managed to hang onto its lunch. They are pretty cute little spiders.