Wedding photography can include photos of the preparation, portraits, the ceremony, the reception, attendees, the venue, and the family.
Usually people get these photos: The ceremonial kiss Some portraits of the couple Individuals of the bride and groom Various family circles The wedding party The bride and groom each getting ready Some silly or romantic poses/photo editing.
Then the work later involves going through and selecting good photos, a lot of back-and-forth with the couple about which they want, touch ups, photo editing, printing and sale. Some photographers offer CD's, individual prints, or assembled albums. Different sizes and quantities mean different prices.
Remember, the photographer owns the rights to the photos, so if the couple wants more they should buy them from the photographer, unless they sold the rights to them.
((My father is a photographer and has done several weddings.))