What's the main difference between "joy" and "happiness?"

Native speaker’s answer
Rebecca
Both "joy" and "happiness" mean the feeling of contentment and pleasure. "Joy" is more about an inward feeling of contentment, and "happiness" is an outward one. People often say that "happiness" is temporary, but "joy" lasts longer, even if things aren't going well. Either way, "happiness" is more commonly used within daily conversation. Ex: Your present brought me a lot of joy. => inward satisfaction Ex: I'm so happy we're going to the movies tonight!