Detailed study of relativistic jets around black hole sources has been carried out considering radiation and
thermal driving. Across the chapters, the investigation is made in various regimes, flat space-time to curved
space-time, fixed Γ to variable Γ relativistic EoS, radial to non radial cross section of the jet, Thomson scattering to Compton scattering regime etc. Acceleration process in jets through thermal and radiative driving is studies and jets with e− − e+ composition are obtained to be achieving relativistic speeds up to Lorentz factors γ ∼ 10 while for e− − p+ composition it is γ ∼ 2 for luminous discs. Further, theoretical evidence of internal shocks are obtained that are required to explain high energy tail of the spectra of radio sources. We obtain that through
Compton scattering relativistic jets are heated by temperature up to T ∼ 1011−12K which is comparable to the obtained values of brightness temperatures in the extragalactic radio sources. A detailed analysis of dependence of jet dynamics upon various parameters like plasma composition, magnetic pressure in the disc, luminosity, accretion rate, jet geometry and jet launching energy etc.is carried out.