The book Flash Boys provides a solid understanding of how HFT got started. http://www.amazon.com/Flash-Boys-Michael-Lewis/dp/0393244660

Flash Boys by Michael Lewis: http://www.amazon.com/Flash-Boys-Michael-Lewis/dp/0393244660

Flash Boys is about a small group of Wall Street guys who figure out that the U.S. stock market has been rigged for the benefit of insiders and that, post–financial crisis, the markets have become not more free but less, and more controlled by the big Wall Street banks. Working at different firms, they come to this realization separately; but after they discover one another, the flash boys band together and set out to reform the financial markets. This they do by creating an exchange in which high-frequency trading—source of the most intractable problems—will have no advantage whatsoever.

Micheal Lewis explains dark pools and HFT's quite well in his new book Flash Boys [1].

[1] http://www.amazon.com/Flash-Boys-Wall-Street-Revolt/dp/03932...