Heat Transfer: This refers to the movement of thermal energy from one thing to another thing of different temperatures. Like passing along whispers in a game of telephone but with heat instead!
Thermal Equilibrium: When two objects reach the same temperature after being in contact with each other for some time. Like when you put ice cubes into warm soda and they both end up at the same cool temp!
Kinetic Energy: The energy that an object possesses due to its motion. Think about swinging on swings - higher you go more kinetic energy!