Do we really have souls??

After reading this... don't think i have a heart made of stone.. because it's not...

First thing, I don't really understand exactly what a soul is. So, this must be the reason why I think there is nothing like a soul (There.. I said it..).
The reason?? No reason. I just don't feel like there just might nothing like a soul. Then how are we alive you say?? Well, I have some explanation for that..

We are living in a world where there are endless machines all around us. The computer or tablet you are using to read this, the air conditioning systems, the cars.. all of 'em are machines. So, why can't we think that we are just way to advance machines? When we die, we just stop functioning. That's it. End of story. Then you will say that if this is the case, them explain this - "We can always revive a machine, from almost any problem. then why can't we bring a dead person to life?"
To this, I have another simple explanation, all those machines which we can revive are those which we have made. About which we understand each bit. The problem with the human body is that its way to complex for us to completely understand it. Me may understand the whole of it someday, and that day, we will be able to revive dead people.
Also, the way i understand it-
for a machine to work properly, each part, each component should work together for the whole machine to work. In our machines, these components are not very small. But if we talk about the human body, there are billions of small components. There are components of components. The organs have tissues, the tissues have cells, the cell have it's own component etc. If, we are able to start all of these components of a dead person simultaneously, we may be able to revive the person. But, this is really difficult to achieve. Since, there are billions of small components.
Then you can say  one more thing, we have feelings and we can think.. this is sufficient to prove we have a soul. Well, we are working on artificial intelligence aren't we? Which will enable computers to think and show emotions. Will you say that we are putting in souls in them? I Don't think so.. It's just the Operating system. Or we can say that we have the most advance operating system in the world in yourself. And if that is what we call the soul?? Then it's okey, there is something like soul but, this soul can not leave the body after we die.. (OS from the computers don't)..
But if I know correctly, soul is supposed to leave the body and so, i think that not believing in souls is a much better idea.   
+Manisha Kashyap  told me that humans do have souls. And that has been proven scientifically, but i think until i hear how, ill stick to my opinion...