What are stablecoins?
Stablecoins are a form of cryptocurrency. Unlike Bitcoin and other speculative coins, however, stablecoins are nominally pegged to underlying assets in order to limit price fluctuations. This stability has made them the currency of choice for buying other cryptocurrencies.
Stablecoins first emerged around 2014 but their use has grown rapidly since the start of this year. In January, there were about $30bn worth of coins in circulation. By October, this had risen to more than $130bn.
There are dozens of types of coins but a handful make up most of the total value: $70bn worth had been issued by market leader Tether by October; another $32bn was in USD Coin, which is jointly run by payment services company Circle and cryptocurrency exchange Coinbase.