Understanding experience*

Most internet stores allow you to buy things, but do you go shopping? Shopping is as much about going to the shop, feeling the clothes, being with friends. You can go shopping and never intend to spend money. Shopping is not about an efficient financial transaction, it is an experience.
But experience is a difficult thing to pin down; we understand the idea of good experience, but how do we define it and even more difficult how we design it?

*) cited from Dix's HCI book