The following website has a slideshow that offers a reasonably good explanation of how the stock market and its clearing mechanisms works, with several case studies, as well as some commentary about the SEC placed in historical context. Rather than trying to synopsize it further, it’s offered for your perusal. The show lasts for about 80 minutes, so be prepared to spend at least that much time listening and watching. As a slideshow, it’s not presented primarily as text, so it’s hard if not impossible to speed it up, making my favorite method of reading fast impossible.
The information presented is worth the time spent watching and listening, even if you have little interest in the stock market. Darkside of the Looking Glass may dispel some myths.