Reincarnation is very real. Almost all humans alive today have had multiple lifetimes in human form on Earth. These lifetimes span time, race, culture, geography and gender. “Younger souls”, we have been told, are obligated to come back to continue with their soul lessons; the same way education through grade school is mandatory. “Older souls” have more choices available to them. All are in a process of education. Even those in the Light World are still learning.
Your present lifetime only really makes sense in the context of the lifetimes that have preceeded it. This is why events that might seem negative, like having a physical deformity, may be exactly what the soul needs in its course of development or to rectify a karmic imbalance or debt.
Most people who think of their past lives imagine themselves (their body, personality, sense of self) existing in a former place and time. That is not the way it works. Who you are in this lifetime (by those same parameters) is unique to this lifetime. Your essential Spirit self is the same, but most of the particulars are not. That is why each moment of each lifetime is precious, unique and irreplaceable.
Furthermore, at the end of each lifetime the body dies but the personality of that life does not. It goes on to The Light, to the Grey Zone or to some other “place” where, from what we have seen, it lives forever. Thus, every person that has ever lived is, on some level, alive today. This is why we are able to talk with people that have physically died but are still very much alive. In fact, it is possible for you to have a conversation with who you were in another lifetime; someone who is You but not you, so to speak.