The title from Bloomberg is misleading and the others here are correct to say that this is more a history of Electronic Clearing. That said, Electronic Clearing

The title from Bloomberg is misleading and the others here are correct to say that this is more a history of Electronic Clearing. That said, Electronic Clearing does allows for increased automated interaction with the exchange spinning off everything we think of today as Electronic Trading(think HFT algo-prop trading, dark pools, reg NMS, etc.). Bloomberg could have also arbitrarily picked ticker tape as an example of how computers (or just technology for that matter) took over Trading. Its a natural progression in a highly competitive industry where speed of information is an essential edge. It would be more poignant to analyze how Reg NMS came to be and what effect that has on the market. Also consider the financial incentive that the exchanges are in as electronic trading has become prevalent. More trades me more commissions. The exchanges WANT higher volumes and more churn. Take what the exchange operators say with a grain of salt.