Origin stories are a major feature of the Dragon Age experience. You choose your origin, and from that starting point, your story begins. You play through your character's early days, defining his or her background and motivation and begin to learn more about the world of Ferelden from your own distinct perspective. Your choice of origin defines how you will view the world and how it views you. Choose a sneaky, disrespected commoner and you will play a story that focuses around subtle skills and careful wordplay. Choose a noble origin and the world will be much more positive and helpful, but those jealous of your status will not be afraid to take what you have, violently if necessary. More will be revealed on these stories soon.
In Dragon Age, your choices change the world and affect the people around you. Certain situations, storylines, and conversation options will change drastically depending on your origin and your motivations.