All forms of matter,whether solid,liquid or gas,consist of atoms or molecules that are in constant motion.All matter is therefore said to contain thermal energy because of this vibrating motion.Whenever a substance is heated,its atoms move faster and faster,which leads to an increase in thermal energy.Temperature is a measure of the average motion of the atoms or molecules within a substance.Heat is the energy that flows because of temperature differences.In all situations, heat is transferred from warmer to cooler objects.Therefore,if two objects of different temperature are in contact,the warmer object will become cooler and the cooler object will become warmer until they both reach the same temperature. There are three mechanisms of heat transfer which are experienced in everyday life,these are: conduction, convection, and radiation.