The molar mass and Atomic mass are both important terms in chemistry. You can easily confuse one for another because both contain the word 'mass.' By definition, molar mass means the mass of a particular element or compound divided by the amount of substance in a mole.
That is the reason why the unit of Molar mass is usually gram/mol. Atomic mass, on the other hand, can be defined as the mass of an atom, which includes the addition of the number of protons and neutrons for that particular atom. Atomic mass does not have any unit. Atomic mass is very important to know, because, without it, you may find it difficult to determine the molar mass of a particular compound accurately.
For instance, to determine the molar mass of NaOH, you should know the atomic mass of the various consistent elements. The atomic mass of Sodium is 23; Oxygen is 16, and Hydrogen is 1. This means the molar mass of the compound is 40 g/mol.