I Studied properties of variable stars briefly. Then in Eruptive variable, I studied the wolf- rayet Stars (WR Stars). As per variability classification, wolf–rayet stars (WR stars) are the evolved stars having spectra formed due the broad emission lines formed by the ionized helium, oxygen and nitrogen or carbon. Mass loss, binnarity, metalicity, rotation, and stellar wind like properties are important to understand nature of different types of WR stars. In WR binary systems, wind interactions during the peristron passage causes X-ray to radio waves emission. Thermal and non thermal emissions observed during such processes are studied during the peristron passage. WR stars are also expected as possible progenitors of some of the Gamma ray bursts (GRBs). I report, a literature survey based on such studies reported in various review articles