Harold Davis has written an excellent article of why one should use Flickr as a method to show, share, and publicize his/her photographs. You can find his article at the following web address.
http://photo.net/column/harolddavis/finding-an-audience-for-your-photography/using-flickr-for-marketing/
If you are unfamiliar with how to register for a Flickr account (it is FREE), read the earlier blog post on this site written by John Flinchbaugh who steps you through the process of signing up and what your many options are.
Charles Heusterkamp, III, M.D., Photographer