Now the definition of publication is changing. Since the early 1990s, with the creation of computer networks like the Internet and now the World Wide Web, academics can communicate immediately and at very little cost. Traditional books and articles, especially those with color, are expensive to print, and take months and even years to produce. With electronic publishing, researchers can include all the data they've collected, so that others can replicate their work. In traditional publishing, it's often too expensive to include tables and tables of data.
Electronic publishing can include other forms of communication, like sound or video.
That's especially important, because price increases in publishing, and cutbacks in funding, have forced libraries to slice the lists of books and journals they buy. Say you were interested in an area's underground geology. Traditionally you obtained data from scholarly articles and the records of wells drilled. Now you can get much of that same information, immediately, via the World Wide Web. As a result, researchers can, in essence, self-publish and bypass peer review.