Wicca is a religion based upon natural magic. It is also known as witchcraft. The craft is not anything evil, nor anything based upon Satan.
Wicca includes the practice of magic. It is important that the magic is natural, and not used for evil. There is nothing supernatural about it. Most tools that Wiccans use are spells, visualization, chants, candles, amulets, and meditation to help focus the power. The tools aren't what cause the power, the power is within you.
Wiccans can either be a solitary practitioner or a coven.
Solitary Practitioner:
It is one person that practices witchcraft.
Coven:
A group of people that practice witchcraft.
Most people ask if they can be Wiccan, even if they believe in the Christian God. The answer is usually, yes, but you won't be considered Wiccan, because the Wiccan Laws mean you have to worship the God and Goddess. You can follow whatever god you may want, but there will be imbalances in the energies used. One problem is that in the Bible it says, "Thou shalt not suffer a witch to live." So it may not actually be right.
"What is a Witch?" is a question most asked. It is answer by someone named Nitewing.
"A witch is a person who, by study, meditation, and practice, have learned the uses of herbs, can read the signs of nature to know tomorrow's weather, have an open ear to the "inner voice", strive for balance and harmony in all things, do not judge diversity but choose to rejoice for it, has power over their own life, communicates constantly with the Lady and Lord, fights against injustice of any kind, wears the name "Witch" with pride, and has love and compassion for all of creation. A Witch is all this and more. A fool, on the other hand, is one who speaks judgement without knowing the facts, or who claims to walk a path they know nothing of."