Big Bang

In general parlance, there are a lot of definitions for the term "big bang." There's the creation of the universe, of course. The last scene of Dr. Strangelove. There's the Rolling Stones album, "A Bigger Bang." There's the TV show, The Big Bang Theory, and its eponymous Barenaked Ladies' penned theme song. There's a Korean boy band BIGBANG. There are some additional ones that are more appropriate for a different part of the Internet.

And in finance, there's a key event in market deregulation.

On October 27, 1986, a number of reforms of the London stock exchange went into effect. Given the sweeping nature of the changes, the day would receive the nickname of the Big Bang.

In order to modernize its financial system, the U.K. government approved the loosening of a number of regulation, and promoted an improvement in technology. This included changes in rules governing commissions and (perhaps most wide-ranging of all) a switch to electronic trading from the previous reliance on open-outcry trading.