All measurable quantities are called physical quantities such as length, mass, time and temperature. A physical quantity possesses at least two characteristics in common. One is its numerical magnitude and other is the unit in which is it measured.
For example, if the height of the person is 130 cm then 130 is its numerical magnitude and centimetre is the unit of measurement. It would be meaningless to state 130 only.
Physical quantities are divided into BASE quantities and DERIVED quantities.
Video by Free Animated Education, explains nicely the concept of Physical quantity as well as Base Quantities and Derived Quantities.
