Online retail giant Amazon.com has acquired US-based print-on-demand company BookSurge LLC.

The privately owned inventory-free book printing and fulfilment company based in South Carolina already provides a print-on demand service for out-of-print or hard-to-find books, available for sale on Amazon.com or as a service to other publishers and authors.

And other retailers, wholesalers and distributors use its wholesale platform, called BookSurge Direct.

But Amazon hopes the deal will primarily allow it to offer more a wider range of more rare titles, including foreign language translations, to its readers.

'Print-on-demand has changed the economics of small-quantity printing, making it possible for books with low and uncertain demand to be profitably produced,' said Greg Geeley, Amazon.com media products vice president. 'Thanks to print-on-demand, "out of print" is out of date.'

Neil Macehiter of technology analyst Macehiter Ward-Dutton says the books Amazon.com will use this acquisition to sell books that are at the 'long tail' of a graph representing the availability of a particular title against number of people interested in purchasing it.

'The interesting thing about the 'long tail' is that the overall sales at the end of the tail may well exceed the products which sell in large amounts - since the tail is so very long,' he said.

He says similar behaviour has been seen with online music services, such as iTunes and Rhapsody, who are able to sell music which it doesn't make sense for a more traditional stockist and retailer like HMV to sell in-store.

Although he added: 'For Amazon it means that it can still sell books, which otherwise it couldn't. I do not think this makes Amazon the 'Dell' of online book sales.'

Amazon.com did not disclose terms of the BookSurge deal.