A witch is a person with the power to effect change by magical means ("Witchcraft"). A witch can be either male or female, as they connect with the elements and forces of nature, in order to practice sorcery.
Magic (or Witchcraft) is the power to effect change by magical means. Magic can often be split into dark and light, though depending on the situation can also be neutral. Magic is both a genetic heredity and a studied technique that connects a person to the elements and forces of nature in order to practice witchcraft.