• The term. “dimension” connotes the defining characteris)ics of an’ entity.

• .The “unit” is a basis for quantification of the entity. For example, length is a diniension where as centimeter-is a unit of length, time is a dimension and the second is a unit of time.

Units and, standards

Dimensions

System of Units

Anum’ber of systemsofunits are in use .since 16th centu.ry. The important systems of unitsaro