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Bitcoin has an image problem. A big one. And it's holding the virtual currency back from going mainstream, said Hank Lucas, a professor at the University of Maryland who focuses on disruptive technologies.

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"It's hard for me to say that bitcoin is going to be the dominant virtual currency of the future," Lucas said. "If someone came up with a virtual currency that people understood and whose value did not fluctuate as much, well, then it might become the one adopted by the masses and not bitcoin."

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There's certainly no shortage of alternate digital currencies—Namecoin, Litecoin and Dogecoin, to name a few. But bitcoin is by far the most popular and widely used of the bunch. Yet, it's too early to tell if its popularity will last, Lucas said.

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One reason bitcoin has gained the level of traction it has is because merchants don't have to pay transaction fees, Lucas said. It's also popular with consumers because it gives them more anonymity when making purchases, he added. But despite its growth, most people remain skeptical of the currency, Lucas said.