Answer:
the Id is basically the most basic component of one's personality. We are born with this and use it in infancy.
it is influenced by what is known as the pleasure principle which gives rise to the humans incentive to satisfy basic needs like eating and drinking among other things.
i.e, when a baby cries and communicates the need for being fed, nursed, changed, etc...
As we get older, the ego comes into our personality development and is guided by the reality principle by acknowledging that we must find appropriate ways to meet our needs since we can no longer cry when we are hungry without looking like idiots and grabbing food from other people is very inappropriate.
Finally, there is the superego that is instilled in us via parents, and other people that influence our concept of the world around us. It serves as our guidelines of what we should and shouldn't do. It works to further suppress the impulses created by the Id and is usually detected in individuals when they are five-years-old.
source: about.com/learn about the Id, Ego, and Superego