This is a true story. A man walks into a Target store and asks to see the manager. The manager asks if he can help and the man produces an advertisement that his daughter had received in the mail at their home. It was for diapers, wet wipes, strollers and other baby gear.

“My daughter is only 16,” the man said. “Why are you sending this stuff?”#-ad_banner-#

The manager apologized profusely and offered a vague explanation. The man nodded and left. A few days later, the manager, who was bothered by the entire situation, called the man to once again offer apologies.

“Well, it appears that I complained too soon,” the man said. “Evidently there are some things going on in my house that I wasn’t fully aware of. My daughter is due in May. So I guess my only question is, how you knew before I did?”

The manager again offered a vague explanation, but the truth is that retailers like Target have complicated algorithms that carefully analyze massive amounts of purchasing data. They can discern buying patterns and draw highly specific marketing conclusions.

In this case, the man’s daughter had bought a number of items in one transaction that expectant mothers tend to buy. Armed with this data and other customer information, the retailer can send out highly targeted marketing material — material designed, in this case, to create a strong bond with a potentially lucrative long-term customer.

Today, retailers are very careful with this sort of customer information. They still analyze the data, and they still make these sorts of conclusions, but they will include other offers to mask the intention of the targeted campaign — a coupon for dog food, say, or patio furniture and other seasonal items.

The truth is, retailers like Target (NYSE: TGT), Wal-Mart (NYSE: WMT), J.C. Penny (NYSE: JCP) and others use “Big Data” to know exactly the kind of ads to get in front of you. But what they don’t want is consumers to know just how much they know about them. Just think how much I could tell about you by examining what you bought at the grocery store. If you think that loyalty card is there to give you a discount, think again. This is how supermarket mailings are eerily matched to the same stuff you typically buy.

As an investor, all you need to know is this: Information is the most important and valuable commodity on Earth, and it always has been.

The only difference is that now an entirely new industry is arising that promises to change the way we eat, play and live. And perhaps most importantly for investors, how we do business.

Today, the ability to use massive amounts of data and strain it into something resembling intelligence — even for something as mundane as what you buy at the grocery store — is a large, growing and dynamic industry.

Essentially, it is the job of a Big Data to store large amounts of information, enable its easy analysis and aid in the presentation of the data’s results.

In 2010, Big Data was a $3.2 billion industry. But research firm IDC expects it to grow more than 428% to $16.9 billion by 2015. That’s a scorching 40% per-year growth rate.

So, what is the best way for investors to capitalize on this opportunity?

Massachusetts-based EMC Corp. (NYSE: EMC) is the 800-pound gorilla of Big Data, with $50 billion of market capitalization and annual revenues in excess of $20 billion. It’s admirably profitable…

There’s just one problem. With the company as large as it is today, the company’s growth prospects have diminished somewhat, though they ought to mirror the industry’s growth going forward.

Another option is a much smaller company, Emulex Corp. (NYSE: ELX). This company has a market capitalization of $529 million — about a hundredth of EMC’s. The share price during the past 52 weeks has been volatile, with a low of $5.72 and a high of $8.67. Its recent price of $5.84 puts it near the bottom of its range for the year.

Even with the stock‘s recent losses, the company’s fundamentals are favorable. Revenues last year came in just above a half-billion dollars, a record, which represents a 9.9% compound annual growth rate during the previous three years. The balance sheet shows a modest amount of cash, no long-term debt, and roughly static shareholder equity for the past several years.

Action to Take –> Big Data has scope — it touches every sector of the economy. I expect companies like EMC and Emulex to be at the forefront of this technology, pushing the outer bounds of what we thought was possible with data — and delivering substantial profits for investors in the process.

P.S. — Just one high-capacity data storage device — like the ones EMC and Emulex make — contains more data than existed on the planet just three years ago. And in five or ten years, it’s possible that maybe only three or four companies will own 99% of the data storage market. In a recent issue of Game-Changing Stocks , I gave a review of four stocks in this space that I think could profit from a golden age for Big Data. To learn how to get this issue and also get my latest report for more ground-breaking investment plays, click here.