The answer to 'which is better water heater or' is that there is no single 'better' option - the best choice depends on your specific needs and situation. Both water heaters and boilers have their own advantages and disadvantages in terms of features, benefits, costs, and use cases.
Water heaters are generally less expensive to install and maintain, and they heat water on-demand rather than keeping a full tank heated at all times. This can be more energy-efficient for many households. Boilers, on the other hand, can provide whole-home heating and hot water, which can be more convenient and cost-effective for some homes. Boilers also tend to have a longer lifespan than water heaters. Ultimately, the right choice comes down to factors like your home's size, energy needs, budget, and personal preferences.