Michael Lewis' "Flash Boys"
High Frequency Trading: Michael Lewis explains what it is and why we are all losing out. His latest book, "Flash Boys", has stirred up the murky world of algorithmic trading on the world's financial markets. Mr Lewis tells presenter Evan Davis what "High Frequency Trading" is, and why he thinks that ordinary investors are losing out in Wall Street's race to adopt ever faster and smarter computers. We hear from Ronan Ryan, who helped set up a new financial exchange aimed at weeding out those deemed to gain an unfair speed advantage from using computers. Also in the programme, Naveena Kottoor reports from Algeria on a very different kind of trading - the black currency market that operates in a public square in open view of the local police.