Moosa Shafiu Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia moosashafiu@hotmail.com International Journal of Fundamental Physical Sciences (IJFPS) 1 4 87-90 December, 2011 2231-8186 https://doi.org/10.14331/ijfps.2011.330021 In this paper, we have used the general nonlinear Schrödinger equation (GNLSE) to study the spectral evolution of a short light pulse propagating through an optical fiber. The equation includes the main factors affecting its propagation through the fibre, involving the linear and nonlinear dispersive characteristics. We find the asymmetry feature of the spectrum due to the Raman Effect. The first order group velocity dispersion sets in after a finite propagation length. We have systematically studied the evolution of the pulse through in a nonlinear medium. Supercontinuum Generation, Nonlinear Schrödinger Equation, Self Phase Modulation, Raman Scattering, Self Frequency Shift https://creativecommons.org/licenses/by/4.0/