What is a Witch?

This is one of the most asked questions.  Unfortunately, there is no single answer.  This represents one way of looking at the answer.  A Witch may or may not be a practicioner of the religion/craft of Wicca. Wicca (as practiced today) is a religion which draws upon certain ideas which predate Christianity, while drawing on modern thinking as well.  It is often refered to as a 'Neo-Pagan' religion, which reflects its reconstruction and/or modification of some ancient beliefs.

There are hundreds of different branches of Wicca, each with its own beliefs, central ideas, area of importance, ideals, etc. Anyone can create their own new branch of Wicca if their beliefs don't quite match up with that of an established coven -- most practicioners do not see their way as being the ONLY way (I certainly don't - religion is a personal thing, and no two persons are the same...). There are a number of common beleifs and views, which may or may not be shared by any given coven.

Here is a general list of beliefs:
 
1.  The existance of a supreme deity/deities. 
2.  The deity is often divided into both male and female aspects.  (although some covens only recognize one gender, usually the Goddess aspect) 
3.  These deities are honored on certain occasions, sometimes refered to as Sabbats and/or Esbats. 
4.  These gods/goddess may have one or several names, one or several aspects. 
5.  The practitioners recognize the existance of a power that exists all about us, and are often trained in how to recognize and manipulate such energies to various effects. 
6.  Most (if not all...) covens adhere to a particualar creed - 'So long as it harms no one, not even yourself, do what you will'. There are many variances to the wording, but the intent is recognized by all. 
7.  Practitioners may be trained in how to understand certain symbological figures that affect both their craft work and their daily lives. 
8.  The number of members in a coven may vary, but as a general rule it is a very small, private, personal religion. 
9.  Many covens have a heirarchy of degrees, the lowest generally being an 'initiate' or 'novice', the highest being a 'high priest' or 'high priestess'. There may be three levels or more. A person who is recognized as being a 'priest' in one coven may or may not be necessarily recognized within another. The degrees usually reflect the amount of training a person has within his own particular coven and in the religion in general. 
10.  Many covens do not recognize the existance of a supreme entity of evil -- negative aspects exist, yes, but too grant enlightenment as we strive to understand Their existence.

I could go on, but that covers a lot of basic ground.  I have tried to leave out absolutes, because the religion is so unique to each person and group. I've been taught to recognize most all branches of Wicca, known and unknown, and I hope my definition is somewhat fitting (if somewhat vague!)

Here are some more writings to get you think:

A Pagan Glossary -- simply one of the BEST sources of definitions on the 'Net
Another View of Wicca -- from Earth Rite
Wicca, Wicca, Who's Got the Wicca? -- by Hurn  A truly excellent article categorizing some of the major elements of Wicca.
More on the W-Word, by Valerie Walker

~by Ma'at (with thanks to Silvernote)