What is driving Bitcoin's recent rally to record highs?

The cryptocurrency Bitcoin hit a record high of almost $20,000 on Wednesday. It has retreated slightly in early trading on Thursday, but some market analysts have said this rally is different from the last peak in 2017, when prices crashed suddenly, while others remain sceptical. Also today, shares in the workplace messaging platform Slack soared on Wall Street, after reports of takeover talks with the software giant Salesforce. Acquiring Slack would bring the cloud computing firm into closer competition with Microsoft.