The first thing to know about Wicca is that it is a nature religion. It is a religion that celebrates Earth's ecology, the changing of seasons, and the power of life. Wicca celebrates the Earth, Sun, Moon, and stars. Wicca celebrates human intelligence and human dignity. Wicca sees consensual sex as sacred, not something dirty or shameful. Wicca puts forth the idea that we are not wholly separated from divinity, nor are we "fallen" or "sinful". There is no "devil" in Wicca.
Wicca is a celebratory religion. Each of the eight holidays affirms the beauty and majesty of each season. There are holidays for the equinoxes, solstices, and midpoints inbetween.
Wicca is a religion that affirms human dignity. Practitioners of this faith do not grovel or prostrate themselves before their gods. We may ask, but we never beg. More often than not, the witch is satisfied being the agent of positive change rather than waiting for some deity to fix things. Wiccans work in tandem with deity but are not slaves to deity.
The moral benchmark in Wicca is "do not harm" instead of "do not sin". The concept of "sin" is arbitrary and comes from old books. But everyone knows when they have hurt someone. That knowledge is natural and innate.
Wiccan is generally a duotheistic religion (with a God and Goddess). However, it is also easily possible to find polytheistic Wiccans.
What Wicca is not
Wicca is not Satanism. The Wiccan faith does not recognize a "Satan", "Devil", or "Hell". It does not recognize the concept of "sin". Wicca generally reveres nature gods and elemental spirits. Wiccans do not seek to bring harm or suffering to others.