What is heat transfer? Give its types.

(N/A) Heat is a form of energy.
Heat transfer is the process of energy transfer from one system to another,or from one part of a system to another,arising due to a temperature difference.
Thus,the movement of heat within a substance or between substances is called heat transfer.
There are $3$ distinct modes of heat transfer:
$(1)$ Conduction: Heat transfer in solids,where energy is transferred through molecular collisions without the actual movement of matter.
$(2)$ Convection: Heat transfer in fluids (liquids and gases),which involves the actual movement of the heated particles of the fluid.
$(3)$ Radiation: Heat transfer that does not require any material medium; it occurs through electromagnetic waves.