Spells are one of many ritual activities that many Wiccans engage in. Not all Wiccans cast spells; they are a matter of personal preference.
Spells can be designed to attempt to either harm or help others. Thus, there are both evil spells and healing spells. The same magickal processes are used for both.
Before performing a spell, Wiccans carefully think through all the possible repercussions of a spell to make certain that it does not have a manipulative component. Wiccans believe that spells alter the course of the universe and are not to be entered lightly without thoroughly considering all of its possible effects.
There are probably as many types and designs of Wiccan spells as there are Wiccans:
Some spells are very simple, consisting of only a few phrases and actions.
The spell may complex and may involve a full Wiccan ritual, including casting a circle, invocation of deities, statement of purpose, working of the spell, meditation, thanking the deities, and closing the circle.