Where the appendage terminates, the hand begins. This portion of the arm on both humans and other primates is what seperates us from several other species, due to our ability to hold onto objects, etc. Several other animals have orfices that are similar to a hand, i.e. that allow them to grasp onto things, some that are even very similar to our hands, they are not scientifically considered to be so. For example dogs and cats have paws.
The most distinguishable feature of hands, is that they most have opposable thumbs (capable of being placed opposite to something). Human hands, of course, are what we are most familiar with, as most of us have two of them ourselves... The anatomy of the human hand consists of a palm, with five digits. The palm is connected to the forearm by a major joint called the wrist. The wrist is very agile, but is not part of the hand, so let's move onto the fingers. The four fingers on the hand are located to the outermost edge of the palm. Their ability to bend over the palm provides the ability to hold onto objects. The thumb is the located on the left most side of the palm and is opposable to the rest of the fingers, meaning that it can be rotated 90 degrees on a perpindicular level to the palm. This characteristic is unlike the other fingers that can only rotate approximately 45 degrees. This characteristic further increases are dexterity.
Names:
From left to right off the palm is our finger, then the index finger, middle finger, ring finger and then the little finger, which is most commonly called the 'pinky'.