Heat can be transferred through materials in three main ways. They are conduction, convection and radiation. In all three cases heat will always transfer from the hotter object to the cooler object.
Radiation is when heat is transferred by electromagnetic radiation. A great example is the sun. Even though you are not near the sun you can feel its heat on a sunny day. The heat is transferred to you by electromagnetic radiation. Another example of radiation is when you sit in front of a campfire and can feel the heat of the fire without touching it.