Nine days and no one has answered?
Let me start by saying that witchcraft is a lifestyle. One can be religious or not and still be a witch.
Wicca is a nature based religion. Some wiccans are witches, some are not. Wicca looks to, and honors the natural cycles of the Universe. It is a fairly new religion but based on very old traditions.
Paganism is an umbrella term and there are a list of definitions.
Way back when 'pagans' were the people that lived in the country and not in the cities. They got this title because they had not been exposed to the up and coming religion that we know to be Christianity. Which leads us to another definition, pagan is anyone who does not follow any of the three Abrihamic religions.
A more modern use of the word represents anyone who follows some nature/earth based faith.
Wicca is a pagan religion, pantheists are pagan, Hoodoo is pagan, and many others.
Most of those who claim pagan are those who follow any of the pre-Christian spiritual traditions, one example, Druids.
Some pagans are simple pagans, just having a deep connection to nature and some are eclectic, working with all the gods and goddesses of old, from all cultures be it Greek, Egyptian, Norse, etc.