Wicca is a form of paganism, there are many, many different forms, too numerous to list, but for example there's
Northern Tradition (Norse Gods)
Celtic
Druidism
There are different kinds of witches too, there's
Hedge Witch
Kitchen Witch
Water Witch
Eclectic Witch (who incorporate a bit of everything)
Solitary Witch
It's not something that's easily explained, you're always learning. We don't have a "head" of our religion, unlike Ministers, Priests, Archbishops or anything. Neither do we have one dedicated place of worship.
Special, sacred places yes, for example, our group often hold rituals at Stone Circles or Forests.
It's a very open minded and tolerant religion, everyone is welcome. We don't harm anyone, there's no sacrifice or anything like that!