Mole
A mole is a measure of chemical mass which is defined by the unit 6.022x1023 atoms of carbon-12. This value is also known as Avagadro's Constant.
Moles are the units used to measure the concentration of a chemical in a solution.
A mole, in chemical terms, should not be confused with a small brown furry animal that can dig up your lawn. Nor with Molarity( denoted by M) which is a measure of concentration of a chemical species/substance in moles per unit volume, commonly per litre (Mol/L)