How can we classify variables and constants based on dimension. Give example for each type?

Explanation

Dimensional variables : Physical quantities, that possess dimensions and have variable values are called dimensional variables.
Eg: Length, velocity, and acceleration etc.
Dimensionless variables : Physical quantities that have no dimensions, but have variable values are called dimensionless variables.
Eg: Specific gravity, strain, refractive index etc.
Dimensional Constant : Physical quantities that posses dimensions and have constant values are called dimensional constants.
Eg : Gravitational constant, Planck's constant etc.
Dimensionless Constant : Quantitie which have constant values and also have no dimensions are called dimensionless constants.