We know that materials are chosen for their properties. Some materials have special properties which make them useful for keeping things warm or cool. Heat travels from a warm place to a cool place.
The heat energy in the coffee travels from the hot liquid, through the ceramic cup (careful it's hot!) and from the cup to our hands and the air surrounding it.
Some materials allow heat to travel through them quickly and easily - these are called thermal conductors. Materials which slow down the movement of heat energy are called thermal insulators.
Metals have a special property, they conduct electricity, which means that they allow electricity to pass through them easily. They are called electrical conductors. Metal wires make up the circuit in the toaster. But we don't get an electric shock each time we use the toaster! This is because other materials do not conduct electricity. These are called electrical insulators are are used to cover the metal parts of the toaster.
Right, with all that in mind let's have a closer look at solids.