Generally no. Conference papers often get collected up and made available to interested parties. If this happens you might imagine your paper "has been made available for distribution" but that's not a publication. Some small specialist conferences do proceed with a presumption that an edited collection will be published and may have a publisher waiting in the wings. But often, not all papers are chosen to appear, and you can't claim publication until it actually happens.
Generally the rules are these
1. At large conferences proceedings may be made available, but that's not a publication. You get your feedback, improve your paper, send it to journal for consideration. Cross your fingers. Unless you are lucky enough to find someone wanting papers to consider for an edited book with a reputable publisher. High quality refereed journals generally count as the best option if the paper is good enough to be accepted.
2. If you are lucky enough to be in a conference that has a publisher waiting, you choose if you want to go this route. If so, you must still wait to make sure your work is actually accepted by the editor.
3. You might choose to go for e-publishing which is now becoming more acceptable but still has a stigma attached by many academics. There are some decent e-journals, but you need to choose carefully.
4. Self-publication really is the final option. There some good reasons why some authors go this route, but it is very much frowned upon in the academic world.
An item is "published" when it appears in print in a journal or a book. Or when it appears online in a recognised e-publication.