Physically, the Aim is pretty much what you'd expect from a modern PlayStation controller. If you look for them, you'll find pretty much all the same controls as the standard DualShock 4: two analog sticks, four face buttons, two bumpers, two triggers, a directional pad, Share and Options buttons and even a button mapped to the DualShock's touchpad button (though no actual touchpad on top.
The PlayStation 4's controller is called the DualShock 4, and is the most drastic redesign of the PlayStation controller since the introduction of the DualShock. It features capacitive touch input, like that of the PS Vita, improved SixAxis motion sensing, a brightly-colored "Light Bar", speaker on the controller, and at 7.4 ounces, the controller weighs less than an ounce more than the Dualshock 3 (6.74 ounces). The Dualshock 4 retails for $59.99 US. The Dualshock 4 was originally intended to look similair to the highly acclaimed Xbox 360 controller, but that idea was put to rest in favour of the more classic and Playstation like side to side analog stick placement that Playstation fans are accustomed to. The start and select buttons are replaced by share and option keys that flank on the top of the touchpad. Note that if you're purchasing the Dualshock 4 seperately for an extra controller, it does not come with a micro-USB cable to charge. Instead you will have to use the one included with your system, buy a new one or simply charge the controllers seperately. It has been confirmed via twitter that the up to 4 PS4 controllers can be used at once which is surprising because thats less than what the PS3 supported.