In just five months, the price of one bitcoin rose from $1,337 (US$997.69) to its all-time-high of $3,704 (US$2,766.56) on May 25.
People buy bitcoins for all sorts of reasons. They range from those seeking to invest in safe haven assets in the face of political instability, speculators wanting to ride the wave of what some regard to be an asset bubble, to purchasers who want to purchase illegal goods anonymously on the dark web.
Since mid-2010, when the highly-volatile currency was worth just 9 cents, it has surged by more than 4 million per cent.
When you add the value of every bitcoin, its current market capitalisation is $49.6 billion - almost half of the value of all cryptocurrencies.
