Bitcoin, the leading digital currency by market capitalization, has grown in value by more than 10 times at its highest point this year, but it has also seen significant plunges in value. Still, a number of cryptocurrencies have managed to come out on top. (See also: Bitcoin Price Takes Backstage as Altcoins Rally.)

To say that 2017 has been a big year for digital currencies would not begin to do the industry justice. In the span of just months, digital currencies have skyrocketed in value, interest, and number. There are new digital currencies being launched to investors every week, and a hoard of blockchain-related startups have followed in their footsteps, often bolstered by major fundraising efforts through ICOs.

In the world of virtual currencies, fortunes tend to move up and down quickly. The space is dominated by volatility above many other factors. These are the largest digital currencies by market cap as of mid-December, 2017.

1. Bitcoin

Bitcoin is the original cryptocurrency and it remains the go-to leader of the space. As of this writing, the market capitalization of the world's top digital currency is more than $284 billion, with a price per coin of nearly $17,000.

There are roughly 16.7 million BTC in circulation, according to coinmarketcap.com. This is all in spite of earlier speculation about a Flippening, in which other digital currencies would permanently take over the No. 1 spot. That has yet to transpire. (See more: "The Flippening": Will Ethereum Take Bitcoin's Place?)

2. Ethereum

Ethereum, the digital token which prompted the rise of the initial coin offering, comes in second on our list of cryptocurrencies by market cap. It is significantly smaller than bitcoin; the current market cap is just shy of $70 billion, with a trading price of about $726 per token. There are just over 96 million ETH tokens in circulation as of this writing.

3. Bitcoin Cash

Bitcoin cash, the spin-off of bitcoin which launched as a result of a hard fork, comes in third on our ranking. The total market cap of this digital currency is about $28.3 billion, with a market price of $1,681 per coin and a total circulation of just under 17 million BCH.

4. Ripple

The No. 4 slot goes to the much-hyped Ripple, with a total market capitalization of more than $18 billion. Unlike the top three digital currencies, the price of each XRP token is very small. As of this writing, it's just under 48 cents per token. On the other hand, the total number of XRP in circulation is quite high. There are close to 39 billion tokens in circulation now.

5. Litecoin

Rounding out the top five is Litecoin, with a market cap of $17.3 billion and a total circulation of more than 54 million tokens.

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