Provide the full names of the following biological molecules:
$(1)$ $FAD$
$(2)$ $NAD$

(N/A) $(1)$ $FAD$ stands for Flavin Adenine Dinucleotide. It acts as a redox cofactor involved in several important metabolic reactions in the cell.
$(2)$ $NAD$ stands for Nicotinamide Adenine Dinucleotide. It is a coenzyme found in all living cells and is essential for energy metabolism,acting as an electron carrier in cellular respiration.