The term altcoin has various similar definitions. Stephanie Yang of The Wall Street Journal defined altcoins as "alternative digital currencies," while Paul Vigna, also of The Wall Street Journal, described altcoins as alternative versions of bitcoin. Aaron Hankins of the MarketWatch refers to any cryptocurrencies other than bitcoin as altcoins.
<>In May 2018, Bitcoin Gold (and two other cryptocurrencies) were hit by a successful 51% hashing attack by an unknown actor, in which exchanges lost estimated $18m. In June 2018, Korean exchange Coinrail was hacked, losing US$37 million worth of altcoin. Fear surrounding the hack was blamed for a $42 billion cryptocurrency market selloff. On 9 July 2018 the exchange Bancor had $23.5 million in cryptocurrency stolen. >
One of the most important problems that any payment network has to solve is double-spending. It is a fraudulent technique of spending the same amount twice. The traditional solution was a trusted third party - a central server - that kept records of the balances and transactions. However, this method always entailed an authority basically in control of your funds and with all your personal details on hand.
On 21 November 2017, the Tether cryptocurrency announced they were hacked, losing $31 million in USDT from their primary wallet. The company has 'tagged' the stolen currency, hoping to 'lock' them in the hacker's wallet (making them unspendable). Tether indicates that it is building a new core for its primary wallet in response to the attack in order to prevent the stolen coins from being used.
There are currently more than 9,000 mutual funds that hold more than $16 trillion in assets. In part because of increased competition for those assets from lower-cost ETFs, mutual fund expenses continue to decline. Expense ratios averaged 0.63 percent in 2016 compared with 1.04 percent in 1996, according to the Investment Company Institute, though some funds levy additional management fees or sales charges that buyers should be aware of before purchasing.
<>In 1983, the American cryptographer David Chaum conceived an anonymous cryptographic electronic money called ecash. Later, in 1995, he implemented it through Digicash, an early form of cryptographic electronic payments which required user software in order to withdraw notes from a bank and designate specific encrypted keys before it can be sent to a recipient. This allowed the digital currency to be untraceable by the issuing bank, the government, or any third party. >
<>As of November 2017, Bitcoin and other digital currencies are outlawed only in Bangladesh, Bolivia, Ecuador, Kyrgyzstan and Vietnam, with China and Russia being on the verge of banning them as well. Other jurisdictions, however, do not make the usage of cryptocurrencies illegal as of yet, but the laws and regulations can vary drastically depending on the country. >
<>Properties of cryptocurrencies gave them popularity in applications such as a safe haven in banking crises and means of payment, which also led to the cryptocurrency use in controversial settings in the form of online black markets, such as Silk Road. The original Silk Road was shut down in October 2013 and there have been two more versions in use since then. In the year following the initial shutdown of Silk Road, the number of prominent dark markets increased from four to twelve, while the amount of drug listings increased from 18,000 to 32,000. >
<>While the country was once home to the world’s most active cryptocurrency exchanges, authorities banned the venues last year and have since moved to block access to platforms that offer exchange-like services. — Fortune, "China Is Said to be Cracking Down on a Cryptocurrency Loophole," 28 Feb. 2018 Bitcoin, however, has become the cryptocurrency standard operating much like U.S. dollar would operate in public currency markets, but in the crypto realm. — Michael C. Dealoia, cleveland.com, "Cleveland-area entrepreneurs are pouring resources into new-currency technolgoy: Tech Czar Talk," 25 Feb. 2018 Some companies, such as KODAK, have promoted cryptocurrency investments in hopes of reviving their flagging businesses. — Mike Rogoway, OregonLive.com, "SEC suspends trading in companies run by former Oregon football star over cryptocurrency 'concerns'," 16 Feb. 2018 >