  The present review article has attempted a compact formalism description of
transport coefficient calculations for relativistic fluid, which is expected in
heavy ion collision experiments. Here, we first address the macroscopic
description of relativistic fluid dynamics and then its microscopic description
based on the kinetic theory framework. We also address different relaxation
time approximation-based models in Boltzmann transport equations, which make a
sandwich between Macro and Micro frameworks of relativistic fluid dynamics and
finally provide different microscopic expressions of transport coefficients
like the fluid's shear viscosity and bulk viscosity. In the numeric part of
this review article, we put stress on the two gross components of transport
coefficient expressions: relaxation time and thermodynamic phase-space part.
Then, we try to tune the relaxation time component to cover earlier theoretical
estimations and experimental data-driven estimations for RHIC and LHC matter.
By this way of numerical understanding, we provide the final comments on the
values of transport coefficients and relaxation time in the context of the
(nearly) perfect fluid nature of the RHIC or LHC matter.
