What is the process called when thermal energy transfers between two objects that are in contact?

The process where thermal energy transfers between two objects that are in direct contact is called conduction. This occurs at the molecular level, where faster-moving (hotter) particles collide with slower-moving (cooler) particles, transferring energy and thus raising the temperature of the cooler object.

In contrast, convection involves the movement of fluids (liquids and gases); it transfers heat through the movement of the fluid itself, creating currents. Radiation is the transfer of thermal energy through electromagnetic waves and does not require a medium, allowing heat to be transferred through a vacuum. The term "thermal transfer" is not a formal term used to describe any specific mechanism of heat transfer and thus does not accurately represent the process being described here.