Thanks to our brain, we have access to things that we have experienced in the past. It’s like having our own personal photo and video album, which we can view and replay whenever we want. From the time we were born, we have been collecting several memories and learning various skills. Over time, all these new things we’ve absorbed make up who we are—even the dreams we experience when we sleep! The combination of all of these things creates our unique personalities, which, even if similar to others, can never be duplicated.