A physical change is a change in which no new substance is formed. The substance may change in size, shape, or state, but it stays the same material. Examples include melting ice, cutting paper, and boiling water.

A chemical change is a change in which a new substance is formed. The original substance changes into something different, and it is usually not easy to reverse. Examples include burning wood, rusting iron, and cooking food.

In short, physical changes affect how something looks or feels, while chemical changes create a new substance.