Google launched Google eBooks on Monday, becoming the third major e-books retailer, alongside Amazon and Apple. The technology giant’s move had been long anticipated and marked a significant development in e-books.

Unlike Amazon and Apple, Google is not selling consumers a reading device. Instead, its books are platform agnostic and can be read on smart phones, desktops, tablets, the Nook and Sony eReader -- pretty much everything except the Kindle.

Google is working with all of the big six major publishing houses -- Random House, Penguin, HarperCollins, Hachette Book Group, Simon and Schuster and Macmillan -- and thousands of smaller publishers to offer more than 250,000 in-print books for sale. Google eBooks will also launch with about 2.7 million public-domain books in its store, which can be accessed for free.

More than 200 independent bookstores nationwide will be able to sell Google eBooks. This is good news for independent booksellers, which for the first time will be able to offer a coherent, competitive e-book alternative to Amazon's. Bookstores that currently use the American Booksellers Assn. Web platform, including local retailers Skylight Books, Vroman's and Book Soup, will be able to sell Google eBooks.

Google eBooks' affiliate program, which will go broader at a later date, will launch one partner: Goodreads.

"For us, it's exciting because it's the first platform where you can buy an e-book that's not tied to one system. We’ve always wanted users to be able to buy ebooks wherever," said Goodreads founder Otis Chandler. Site visitors who click a book's "buy" button on the site are taken to a page that lists multiple vendors and formats for sale. "As e-books grow in adoption, I think this should be very interesting."

Readers will use Google eBooks Web Reader, also launching Monday, to read its e-books. Most devices will not download the book but store it in "the cloud" -- an online e-bookshelf connected to a Google account. Google eBooks can be accessed from any device using that account.

Most of the millions of books that Google scanned from major world libraries will not be available until the litigation surrounding the Google book-search settlement agreement reaches its conclusion. When that does happen, it is expected that those books will be rolled into Google's ebookstore.

-- Carolyn Kellogg

Read more about how the ebookstore will work on our Technology blog.