What is a Soul?

I have never really felt like I understood what exactly people meant when they said soul. If I had to define it I would say that your soul is just your internal sense of self, your own sense of who you are or the you that you are in your head. Dictionary.com defines a soul in many different ways, but here are the ways that I find the most relevant.
1.the principle of life, feeling, thought, and action in humans, regarded as a distinct entity separate from the body, and commonly held to be separable in existence from the body; the spiritual part of humans as distinct from the physical part.
2. the spiritual part of humans regarded in its moral aspect, or as believed to survive death and be subject to happiness or misery in a life to come: arguing the immortality of the soul.
3. the disembodied spirit of a deceased person: He feared the soul of the deceased would haunt him.
4. the emotional part of human nature; the seat of the feelings or sentiments.
5. a human being; person.
I think these definitions help to clarify my own position. A soul is not your human body, but your mental existence. It your sense of individuality, humanity and self. Some of the definitions include ideas about the afterlife and assume that your essence or soul will survive your body's death. In regards to robots and their potential rights I can image a robot with the self awareness and personality that would make me think that it does have a soul and deserves rights. However I don't know that I would be able to believe that a man made being's essence or soul would live on after it was destroyed or shut down. If a robot can't have a soul that lives on after system shutdown then presumably we don't have to worry about robot conversion. If we ever do reach I time when robots are given rights and recognized as sentient I think that it may bring about questioning of the widely held belief in life after death. After all, if robots can seem human to people, but we deny that they can have some sort of afterlife what makes us so sure that we will have an afterlife?