Reincarnation is the process of living, dieing, and then living again. It literally means to "come again in the flesh". There are many different views of how reincarnation actually works, especially since no one can actually prove their theory. Reincarnation is one of the Wiccan beliefs, but of course, not all Wiccans or Pagans have to believe this.
Many people believe that when you die, your soul goes to a place called the "Summerlands". It is like a resting place before you go on to your next life. When you go on to your next life, you don't really remember your previous ones (which is obvious), but some people are lucky (or sometimes unlucky) enough to have visions of their previous lives, whether in dreams, d�j� vu episodes, or the like.
Do you feel that you have a connection with a certain animal? Another, but less popular, belief is in transmigration (or metempsychosis), meaning "change of soul". This is the thought that when you die, your soul doesn't have to be reborn as a human, but can actually cross into other animals (some believe plants along with animals) as well. This could explain someone's love for cats, longing to run with the wolves, or just the urge to go run and jump in the sea.
Because of the fact that the world population is growing, more and more new souls are being born all the time. This could explain the world's moral and social downturn. The newer souls are not wise enough to understand the effects of their actions, and can't grasp the fact that what they do now isn't going to just go away. Along with this, most people that believe in reincarnation also believe that what you do in one life will be carried down into the next. This is called Karma. For example, if you are a mass murderer in one life, even if in the next you are raised in a kind, loving home, your life will not be as pleasant as it could have been if in the previous life (or lives) if you were kind and peaceful. Your soul can gradually change with each life for the better (or worse) if you do your best to try to change yourself. No matter how hard things are, if you work to make your life the best it can be, your next life will be more rewarding.
My personal belief is that when you die, your spirit still roams about the Earth (thus one of the reasons for possible "ghost sightings"), and you can chose whether or not when, or if, you will go on to another life. In this little spirit world, I think that you remember all your past lives, and can chose to be what you will be incarnated next as. I don't think that my past life was very fulfilling, but I do think that my soul is relatively old. Along with all this, my little speach up above about how the world is crashing down is one of my huge problems with most of society today, but I mainly attribute it to the growth in population. :)
Only one in four people today believe in reincarnation, but the fraction steadily rises with each year, and with more and more people turning to pagan religions. Just because you're pagan doesn't mean that you have to believe everything that many other pagans of the same religion believe, nor does it mean that you have to believe every single part of it, neither. Forming your own beliefs to what you feel most is probably the best for most, anyways, so feel free to explore all possibilities!!!