image management

am new, so please don’t skip the obvious thinking i know it!

Do i have to re-upload and use multiple iterations of the same image to attach them to different slideshows etc? Or is there a way to attach one image to multiple pages? I am developing a photography portfolio, and would like to showcase images in a general slideshow on the main page, and in a slide-show on the category page, plus have that link to a page dedicated to that particular image. But having to upload the same image several times doesn’t seem terribly efficient. It’s getting really cumbersome.

please help! I have been working on this for days ;-/