Molarity

Molarity is the number of moles of a solute present in one litre of solvent. Denoted by (M).

Molality

Molality is the number of moles of solute present in one kg of solvent. Denoted by (m)

Normality

Normality is the number of gram-equivalent weights of solute present in one litre of solvent. Denoted by (N)