Self-publishing is the publishing of books an other media by the authors of those works, rather than by established, third-party publishers. Although it represents a small percentage of the publishing industry in terms of sales, it has been present in one form or another since the beginning of publishing and has seen an increase in activity with the advancement of publishing technology, including xerography, desktop publishing systems, print on demand, and the World Wide Web. Cultural phenomena such as the punk/DIY movement, the proliferation of media channels, and blogging have contributed to the advancement of self-publishing.