 The hydrogen bond is very strong, takes a lot of energy to break and it's reason for many of the unique properties of water. For instance, it's the reason why water has such a high melting temperature, which is great for us because it means that Earth is in this Goldilocks zone. Another point of the hydrogen bond is that the distance between the melting temperature and the boiling temperature spans a large range of temperatures. Which means for us on Earth, we've got a large range of temperatures in which we can have the liquid water can actually exist. Another interesting point of the hydrogen bond is that when water is in different phases, so when water is in the solid phase, which bonds tend to occupy a much larger space than they would when they're in the liquid phase, where they're able to actually roll over each other and sort of come together, which means the molecular structure of ice is less dense than that of water, which is the reason why ice floats. And this is very important because if ice didn't float, it would sink. The regions of Earth that are ice-prone, such as the high-latitude oceans or the rivers, certain rivers and lakes, would actually fill up with ice and become inhabitable.