* Elements: An element is a pure substance that cannot be broken down into simpler substances by chemical means. They are the basic building blocks of all matter. Examples: carbon (C), oxygen (O), gold (Au).

* Molecules: A molecule is formed when two or more atoms bond together. These atoms can be the same element (e.g., oxygen gas, O2) or different elements (e.g., water, H2O).

In summary:

* Elements are the foundation, while molecules are the structures built from them.

* A molecule can contain one type of element (like O2) or multiple types of elements (like H2O), but it is not an element itself.