What is the meaning of "black hole" in Hawking's A Brief History of Time-From the Big Bang to the Black Hole?

A black hole is a situation in which all matter is compressed in a very small space due to its own gravity after a massive celestial body loses its luminous ability. This huge celestial body is more than eight times that of the sun. If it is too small, gravity is not enough to form a black hole. At this time, all matter near the black hole is attracted to the black hole, including light. If this celestial body has not lost its luminous ability, that is to say, it still has enough substances with small atomic weight to form substances with large atomic weight without nuclear fusion, then it will maintain a high temperature in the process of nuclear fusion, and the high temperature will make the celestial body have enough volume. Because of its large volume and large distance between materials, it is impossible to form greater gravity. Then this celestial body will continue to glow and heat. Here we will think of a question, what is the atomic weight of a small atomic weight? The answer is about iron (atomic weight 56). When substances smaller than iron are polymerized into iron, they will release heat and reach a more stable energy state. In the absence of sufficient pressure, substances greater than iron tend to decay into iron substances (note that it is a trend, not a fact) and reach a stable energy state. Ah!