What is resistivity? Write its unit. On what factors does resistivity depend?

(N/A) At a given temperature,the resistance $R$ of a material is given by:
$R = \rho \frac{l}{A}$
Therefore,the resistivity $\rho$ is defined as:
$\rho = \frac{RA}{l}$
Definition: The resistance of a conductor having unit length and unit cross-sectional area is called resistivity or specific resistance.
Factors affecting resistivity: The value of resistivity depends on the type of material of the conductor,temperature,and pressure.
Note: It does not depend on the dimensions (length or area) of the conductor.
Unit: The $SI$ unit is $\Omega \cdot m$ (Ohm-meter).
Dimensional formula: $[M^{1} L^{3} T^{-3} A^{-2}]$.