While you can't make water hotter than its boiling point at a given pressure, you can boil it for an extended period, causing it to evaporate completely. This can damage your cookware.
Boiling water occurs when the water reaches its boiling point, which is 100°C (212°F) at standard atmospheric pressure. Once the water reaches this temperature, adding more heat doesn't increase the water's temperature further. Instead, the added energy is used to change the water from a liquid to a gas (steam) through a process called evaporation.
'Over-boiling' doesn't mean the water gets hotter than 100°C (at standard pressure). It means you've continued to apply heat after the water has reached its boiling point, causing it to evaporate. If you continue to boil water for a very long time, all the water will eventually turn into steam, leaving your pot empty and potentially scorching or damaging it. Minerals and impurities in the water can also become more concentrated as the water evaporates, potentially leaving residue in your pot.
Always monitor water you're boiling, especially if you're using it for cooking. Setting a timer can help you avoid accidentally boiling away all the water and damaging your cookware.