In this talk, I will give a brief history on Cosmic String as a topological defect produced in the very early universe.  It has been demonstrated that  based on two most popular models, namely supersymmetric Hybrid Inflation and Brane Inflation,  cosmic strings can be formed during the phase transition at the end of inflation.  Previous studies  showed that at time after the phase transition a network  of long cosmic strings will survive. From cosmological point of view, one can divide the strings into loop and long strings. These two kinds of strings can leave imprint in the observational cosmology. The so-called Kaiser-Stebbins (KS), lensing and Pulsar timing are some important imprints of cosmic strings. In this talk I rely on the KS effect and search for cosmic strings and superstring on the CMB fluctuations. I show that since the discontinuity produced by strings on the CMB map to be lost in Fourier space so the global footprint don't give desired result. Consequently, every analysis in real space to be appreciated in this road map.