The concept in psychology that I will remember five years from now would most definitely be the concept of sleep. Rather it be REM sleep or Non REM sleep, we live a large portion of our lives in sleep mode and it was truly interesting to learn about the type of things that can happen between the time we close our eyes to the opening of our eyes the next morning or before. Learning about sleep disorders like the sleep cycle, sleep apnea, sleep paralysis, sleep deprivation, sleep debt and sleepwalking was a huge treat. Because so many of us and our family or friends have sleeping disorders and sometimes don't understand the reason why these things are happening to them or their children, it was fun to learn about how these disorders happen and what to do to cope (for parents) and or treat. I have had the gift of leaning about sleeping disorders and the information that revolves around them, but usually you would need to visit a doctor or professional in order to gain this knowledge. I have bought the psychology book for a reasonable price and now hold the knowledge that a lot of others would have to pay a lot more money to gain. Having this information will be helpful throughout life. Thanks.