That’s a powerfully loaded question…
The simplest way to define it is: self-publishing is the act of getting your own book to print, distributing it, and then marketing it. That said — there are some authors who prefer to create their own books from the ground up. While this can be done – is it always the most feasible option available? Not usually.
Authors can also decide to hire the services of a self-publishing company, which some incorrectly label as “vanity presses”. A vanity press is an outfit that offers little to no support for the author and actually allows them very little involvement in the process of making their book. Naturally, authors should be very careful when dealing with such companies because they may not end with what they are looking for in the end.
However, a full-service self-publishing company will keep you involved in the process and offer support before, during, and after you publish your book. The biggest reason why an author would choose to go this route is if they need assistance creating their book. All authors are not cover designers, book blockers, and marketers. So, they enlist the expertise of a team who knows the book publishing industry inside and out. It’s honestly no different than paying a plumber to fix your toilet. Sure, you can research, study, and practice fixing it yourself. But, do you really want to commit all of the time required to do it?
DISCUSSION: Have you worked with a company to publish your book or did you do it all yourself?
Self Publishing Advisor 
I’ve been looking through your posts, and I really appreciate your upfront approach. For myself, I am more drawn to doing all the leg work myself when it comes to self publishing. Then again, I come from a family of entreprenuers and I am training scholastically to become a publisher. Though, if given the right tool set and the right mind set, whether trained professionally or not, I do think people would be better off publishing themselves and outsourcing the tasks they cannot do on their own (i.e. printing, distribution, and so forth). I see you have been posting since August 2008. That takes a lot of time and drive to publish regularly, so you must have a passion for this subject. So tell me, what thought initially pushed you to publish this blog (besides your own professional links to outskirts press)?
Hi, there:
The biggest (and only) goal is to give authors the information they need to know about publishing. That takes quite a bit of effort to go through the self-publishing process yourself. That certainly takes even more time and drive than posting to this blog. But I do believe that others can do it…but in theory — should you do everything you can do? Not necessarily — that’s what our services are for. If that be the case, we would all fix our own cars, plumb our own toilets, etc. Every person has their strong suits and I think it’s admirable that you are pursuing this yourself.
Thanks for the comment!