Examples of conductors are metals(silver, copper and aluminium, etc), mercury, earth, etc. Examples of insulators are non-metals (plastic, glass, pure water, sulphur, etc). Some exceptions that are non-metals but not insulators are graphite and tap water.
Uses of good conductors
The following are some uses of good conductors of heat
Cooking utensils are made from good conductors of heat such as copper, brass, steel, aluminium etc.,as the utensils get heated up quickly and food can be cooked efficiently in shorter time.
Mercury is used in a thermometer as it is a very good conductor of heat such that it acquires the temperature to be measured by the thermometer.
Copper being a good conductor of heat is used in electric geyser, to conducts heat from the heated element to the water in the geyser.
The bit of a soldering iron is made of copper. As the tip of the hot bit comes into contact with the material to be soldered, heat is rapidly conducted from its heated parts to its tip. So the temperature of the tip becomes more than the melting point of the soldering material and the soldering material gets melted soon.