Step-by-step explanation:
When electromagnetic waves travel through the space and does not require any medium to travel through then it is known as radiation.
Radiations are able to transfer heat. For example, radiations from the Sun help in heating of Earth.
Whereas when two objects of different temperature are placed together then it results in transfer of heat from hotter object to cooler object.
For example, when a metal spoon is placed inside cup of a hot tea then the spoon get heated up after sometime.
On the other hand, convection is a process in which fluid moves due to heat current where hotter material (less dense) rises at the top and colder material (more dense) sinks at the bottom.
Thus, we can conclude that heat is transferred on Earth through radiation, convection and conduction.