A virtue is a good habit. To influence our lives in a deeper way, norms need to be internalized into our character. For example, the golden rule needs to be so much a part of us that we follow it instinctively, as if it were part of our nature. A good person is a person of excellent character traits, a person of virtue.Ancient Greek virtue ethics
These questions are about Chapter 12 of Harry Gensler's Ethics: A Contemporary Introduction (Routledge: 2011).
Moral philosophy started in ancient Greece when Socrates asked questions about virtue and encouraged people to think about such questions in a rational way.
For Plato, who was Socrates's star pupil, the lower must depend on the higher. And so our soul needs to control the body, and our soul in turn needs to be guided by the Good, which is an objective pattern that our minds can grasp. There are four main virtues: wisdom, self-control, courage, and justice. St Augustine and other Christian thinkers accepted this but added three theological virtues: faith, hope, and love.
Aristotle discussed many virtues, but divided them into two main groups: intellectual virtues and moral virtues. Virtue is a mean between extremes; so courage, for example, is midway between cowardice (having too much fear) and foolhardiness (having too little fear). We need practical wisdom to pick the virtues and determine the mean. Virtues aim at happiness, which is the ultimate goal of our actions.