(1) Heat: heat flows from a hotter object to a colder object. In solids, heat is generally transferred by the process of conduction. Materials that allow flow of heat easily are called conductors.
Eg. Metals such as aluminium, Iron, Copper.
Water and air are poor conductors of heat.
Convection: when water is heated from below, water near the heat source becomes hot and rises; then the water from sides comes in to take to place. This process continues till the whole water gets heated; this mode of heat transfer is called convection.
Eg. Sea breze (day time); land breze (night time): COAST
Radiation: this mode of heat transfer does not require any medium. When heat falls on some object, a part of it is reflected, a part is absorbed, and a part may be transmitted. Dark objects absorb more heat, light objects reflect more heat.