The jumping spiders, unlike the other families, have faces that are roughly rectangular surfaces perpendicular to their direction of motion. Their eye pattern is the clearest single identifying characteristic. They have eight eyes, as illustrated. Most diagnostic are the front row of four eyes, in which the anterior median pair are more dramatically prominent than any other spider eyes apart from the posterior median eyes of the Deinopidae. There is however a radical functional difference between the major (AME) eyes of Salticidae and the major (PME) eyes of the Deinopidae; The large posterior eyes of Deinopidae are adapted mainly to vision in dim light, whereas the large anterior eyes of Salticidae are adapted to detailed three-dimensional vision for purposes of estimating the range, direction, and nature of potential prey, permitting the spider to direct its attacking leaps with great precision. The ALE (anterior lateral eyes), though large, are smaller than the AME and provide a wider forward field of vision.
The rear row of four eyes may be described as strongly bent, or as being rearranged into two rows, with two large posterior lateral eyes furthest back. They serve for lateral vision. The posterior median eyes also have been shifted out laterally, almost as far as the posterior lateral eyes. They are usually much smaller than the posterior lateral eyes and there is doubt about whether they are at all functional in many species.