A gas boiler is a heating system that uses natural gas or propane to generate heat for residential or commercial spaces. It works by burning gas to heat water, which is then circulated through pipes to radiators or underfloor heating systems, providing warmth to the environment. Gas boilers are known for their efficiency and can be a cost-effective option for heating. These boilers come in various types, including combi boilers, system boilers, and regular boilers, each designed for specific heating needs. Regular maintenance is essential to ensure safety and efficiency, as improper use can lead to issues like carbon monoxide leaks.