Molar mass:

The mass of one more of substance is called as molar mass.

Examples:

For instance, water exists as molecules therefore, one mole of water contains 6.02 x 10²³ molecules of water. Hydrogen exists H₂ molecules, so one mole of hydrogen contains 6.02 x 10²³ molecules. Carbon exists as atoms so 1 mole of carbon contains 6.02 x 10²³ atoms.