Photographers use and have used both negatives and transparencies to make photographic prints. Transparencies are the same as negatives but the image is positive (normal). Many photographers make slides (transparencies in cardboard holders) to both keep on record and make photographic prints. Transparencies and slides can be easy to date due to format/text/design on the film and/or slide holder.
Just because I have them at hand, these are two of my favorite negatives (made positive to show). They're Karl Lagerfeld photos of Danish model Helena Christensen, shot for his fashion catalog. Lagerfeld shot all of the photos for his catalogs.
