I want boiler troubles and types and prevention,cure,advantages and disadvantages of boiler troubles

How many different types of boilers are there?
There are two general types of boilers: ''fire-tube'' and ''water-tube''. Boilers are classified as "high-pressure" or "low-pressure" and "steam boiler" or "hot water boiler." Boilers that operate higher than 15 psig are called "high-pressure" boilers. A hot water boiler, strictly speaking, is not a boiler.
What is a boiler feed water system?
Boiler feedwater is an essential part of boiler operations. The feed water is put in to the steam drum from a feed pump. In the steam drum the feed water is then turned into steam from the heat. After the steam is used it is then dumped to the main condenser.
What is meant by boiler corrosion?
Boiler corrosion is the active destruction of sound boiler metal by the pitting action of dissolved oxygen in the boiler water. This usually results in deep holes in the metal which are self protected by further corrosion products ie scabs or blisters over the hole which allow the chemical reaction to continue.
What is makeup water?
makeup water. Water which is supplied (as to a steam boiler or cooling tower) to compensate for losses by evaporation and leakage.