As the ice cube gains more heat, its temperature increases. However, there is an important difference between heat and temperature. Notice that they are both at the same temperature but that the bath water has much more heat. Heat takes into account not only the temperature but also the mass of a substance. Temperature is a measure of the average speed of the atoms or molecules in a substance.
Heat always flows from regions of higher temperature to regions of lower temperature.
Heat can be transferred by conduction, convection, or radiation. During a hot summer day, you place a cold can of soda on your cheek. Heat is conducted away from your cheek to the pop. A hot air furnace produces heated air that rises to the top of a house. The cool air moves to the bottom of the house.