One of the most interesting parts of psychology to me is how we are able to retain information. As most people know, we have long term memory and short term memory. However, there is a lot more involved in the process of determining which information we store and hold on to in our minds.
When an event first occurs, chemicals in our brains creates the knowledge of an event happening. These chemicals create what we refer to as "Short Term Memory". (http://www.sharpbrains.com/blog/2006/10/29/how-do-we-remember-a-neuroscience-explanation/) Once we have the initial snapshot of the event that we are remembering, many reactions need to take place between chemicals in our brain. If this does not happen, we will forget the event. If the reactions take place, a permanent memory is created and that is what we refer to as "Long Term Memory".
No matter which part of the memory an event goes into, there is an incredibly complicated process which leads to the simple action of remembering. That is one of the main reasons why I find the human memory process so fascinating. If scientists can figure out a way to manipulate whether our long term memory is used in any situation, we will be able to freely control our memories. Do you think that would be a useful discovery in the near future?