What are the differences between ATP and NADH+H⁺/NADPH.Are both these compounds used as energy currencies?

ATP

Adenosine triphosphate. An adenine molecule, or a nucleotide , attached to three linearly connected phosphate groups (–H ₂ PO ₄ R, where R is a functional group). The breaking of chemical bonds between the 2nd and 3rd phosphate groups provides most of the chemical energy used by a cell. Most of the ATP in a cell is made in the mitochondria, the cell's powerhouse. ATP is a coenzyme (the -ase in the name gives it away) and a strong reducing agent, or electron donor, that acts as the principal energy carrier in the cell. Donating the terminal phosphate group, or the phosphate group on the end, from ATP causes the release of a large amount of energy. ATP basically shuffles energy around to support metabolism and a bunch of super important cellular processes, like photosynthesis.

NADPH

Nicotinamide adenine dinucleotide phosphate, which is a strong reducing agent, or electron donor, as well as a coenzyme. NADP⁺ is the common notation for the non-reduced form, and NADPH is the name once it has been reduced, or gained an electron. NADPH acts as a carrier of electrons and is used extensively in the synthesis of biological molecules.