Both ATP (adenosine triphosphate) and ADP (adenosine diphosphate) contain the following molecules:

* Adenine: A nitrogenous base.

* Ribose: A five-carbon sugar.

* Phosphate groups: ATP has three phosphate groups, while ADP has two.

The difference between ATP and ADP lies in the number of phosphate groups they possess. ATP has three phosphate groups, while ADP has two.