electrical resistivity (also called specific electrical resistance or volume resistivity) and its inverse, electrical conductivity, is a fundamental property of a material that quantifies how strongly it resists or conducts electric current. a low resistivity indicates a material that readily allows electric current. resistivity is commonly represented by the greek letter ρ (rho). the si unit of electrical resistivity is the ohm-meter (Ω⋅m). for example, if a 1 m × 1 m × 1 m solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is 1 Ω, then the resistivity of the material is 1 Ω⋅m.
electrical conductivity or specific conductance is the reciprocal of electrical resistivity. it represents a material's ability to conduct electric current. it is commonly signified by the greek letter σ (sigma), but κ (kappa) (especially in electrical engineering) and γ (gamma) are sometimes used. the si unit of electrical conductivity is siemens per metre (s/m).