From our wedding day to where we left the car keysfrom the trivial facts to the monumental events. Memories form the landscape of our lives and build a bridge between where we have been and where we are going, without memory we would be lost. Although we depend on it every day, how much do we really know about how it works? Today researchers exploring the frontiers of memory are coming closer to discovering the biological mechanisms of how we remember and why we forget. They are racing toward their goal of producing a pill that could help us remember forever. Would you want a photographic memory? Before you answer meet a man who can’t forget. A man with no memory, known by his initials H.M., lead scientists to the first major break through in studying memory, that there are different kinds of memory that involve different parts of the brain. For over 30 years H.M. has been studied at MIT, he has profound memory loss at 23, he had epilepsy and surgery to remove part of his brain in an attempt to relieve his symptoms. It worked, but 59 years old at the time the documetnary was filmed, he only remembers the first 16 years of his life and cannot hold onto a memory for more than a few minutes. He lived completely in the present and has lost his explicit memories. He has the skills he learned growing up, how to walk, talk, eat and shave, those are implicit memories. Scientists now know the part of his brain that was removed is responsible for explicit memories and the part remaining is responsible for implicit memories.