Your skin sensors send a message to your brain that your skin is receiving heat. Depending on the amount of heat you receive, your brain can determine whether an object is hot or cold. If an object is colder than your skin, heat is transferred from your skin to the object. Your skin loses heat, and your brain determines that the object is cold. In other words, whether something feels cold or hot depends on whether your skin loses or gains heat.
All materials conduct heat, which means that molecules bump into each other and transfer heat.
But not all materials conduct heat at the same speed. Conductors are materials that conduct heat quickly, and insulators are materials that conduct heat more slowly. Don't miss Janice VanCleave's new book Science Around the Year .