An elastic collision is a type of collision where two objects collide and then separate without any loss of kinetic energy. In this process, both momentum and kinetic energy are conserved. This means that the total energy and momentum before the collision are equal to the total energy and momentum after the collision. Common examples of elastic collisions include the interactions between billiard balls or gas molecules. In these cases, the objects bounce off each other, maintaining their speed and direction, while the total energy in the system remains unchanged.