Here's the breakdown:
* Magic itself isn't inherently good or bad: In the Harry Potter universe, magic is a neutral force. It's the intention and purpose behind the magic that determines whether it's considered "light" or "dark."
* "Light" magic focuses on healing, protection, and helping others: This is what most students at Hogwarts learn and practice. It's often called "white magic," but the books don't use that term directly.
* "Dark" magic is used for selfish, destructive, and harmful purposes: This includes curses, jinxes, and other spells that inflict pain, death, or control over others.
* Voldemort and the Death Eaters use dark magic: They embrace the power of dark magic and use it to achieve their goals, which are often based on power, control, and prejudice.
* Even "good" characters can use "dark" spells: For example, Dumbledore uses the unforgivable curse "Imperio" (mind control) in the books, but only to prevent a greater evil. He also uses dark charms and spells in certain situations.
So, while Hogwarts teaches primarily "light" magic, the lines between light and dark can be blurry. There are gray areas, and even "good" characters can employ "dark" methods when they believe it's necessary.
It's important to remember that the Harry Potter series explores the complexities of good and evil, and that magic, like most things in life, can be used for both positive and negative purposes.