What Is the 'Goldilocks Zone' of a Star?

Goldilocks Zone is like a perfect spot for a planet to live. It's not too hot, and it's not too cold, just right for water to exist, which is essential for life as we know it. Imagine the planet is like Goldilocks trying out different bowls of porridge: one was too hot, one was too cold, but the middle one was just right!