Heat conduction (or thermal conduction) is the movement of heat from one solid to another one that has different temperature when they are touching each other. For example, we can warm our hands by touching hot-water bottles. When the cold hands touch the hot-water bottle, heat flows from the hotter object (hot-water bottle) to the colder one (hand).
Other ways to transfer heat are by thermal radiation and/or convection. Usually more than one of these processes happen at the same time.