The idea is to give readers the chance to sample books online in much the same way they would if they were in an actual physical bookstore. "This is analogous to removing the shrink wrap from a book," said Jane Friedman, President and CEO of HarperCollins Worldwide.

"The advantage of our digital warehouse is that we can securely, quickly and easily change what content is available, whether it is to meet an author’s request, to preview a title before it is on sale, or to promote backlist books."

Starting today, readers who visit the HarperCollins Web site will be able to view the complete contents of  "The Witch of Portobello" by Paul Coelho; "Mission: Cook! My Life, My Recipes and Making Impossible Easy" by Robert Irvine; "I Dream in Blue: Life, Death and the New York Giants" by Roger Director; "The Undecided Voter’s Guide to the Next President: Who the Candidates Are, Where They Come from and How You Can Choose" by Mark Halperin; and "Warriors: Into the Wild" by Erin Hunter.

Brian Murray, president of HarperCollins, said the free electronic editions would be available for only one month, and readers would not be able to download them to their PCs or an electronic reader like Amazon’s Kindle, according to the New York Times. The print function will also be disabled, but readers will be able to link to retailers to purchase copies of the books.

Freidman said she did not believe most people would read the complete versions online, but HarperCollins would monitor the editions to see if they increased sales. "We will know very soon if we sense any kind of cannibalization," she said.