What is the habitable zone or “Goldilocks zone”?

https://science.nasa.gov/exoplanets/what-is-the-habitable-zone-or-goldilocks-zone/

https://en.wikipedia.org/wiki/Habitable_zone

https://zh.wikipedia.org/zh-tw/%E9%81%A9%E5%B1%85%E5%B8%B6 

環恆星適居帶（circumstellar habitable zone, CHZ）簡稱宜居帶（habitable zone）