Shipping address is nothing but to which address the purchased item should be sent.If seller has given shipping charge for the product then it will be included along with the product cost.

Billing address is nothing but you are purchasing an item that you are going to send it to your friend in this case the billing address is to whom the product cost will be received from.
To change your Shipping/Billing address
1)Click to “shipping/billing” address tab
2)Go to “Edit” page to make change on address