Online retail is already big business in the US and Amazon is by far the largest player in the market. Its recent foray into e-books has also proven quite profitable, creating a new market for e-books and e-book readers that is becoming hotly disputed. Now Wal-Mart, one of the largest brick-and-mortar retailers in the US, is going against Amazon on both fronts with huge discounts on 10 eagerly anticipated hardcover books including Stephen King's "Under the Dome" and Sarah Palin's "Going Rogue" but the online retail giant isn't taking it sitting down.

As Cnet reports, Wal-Mart recently dropped the prices on 10 books to just $10 on the company's online store Walmart.com. With hardcover books usually going for around $30 to $35, the discount is significant but the price point wasn't exactly random. $10 is what e-books on Amazon's Kindle store go for, and the digital alternatives are becoming a growing threat to good old-fashioned books. Wal-Mart doesn't have an e-book store at the moment so it had to fight back in the only way it could, with prices.

Amazon though wasn't going to let it slide so it too dropped the prices on all 10 titles to the same $10 Wal-Mart was charging. Wal-Mart then dropped the prices again to $9 hoping to best Amazon's offer but this was then matched by Amazon again and both companies now offer the 10 books for that price. What's more, Amazon has also dropped the price on the e-book versions of the titles to $9 as well, seeing as it would have a though time trying to sell them for a higher price than the hardcover versions.

In the short term, it's the customers who benefit, though there aren't that many companies that could afford to sell the books at a loss, which is what both Amazon and Wal-Mart are doing, and just wait for the competition to go out of business. Amazon would much rather sell the e-books as it can take a much bigger profit margin on those but it can't afford to lose out on the hardcover sales just yet.