Резюме: Gamma-ray bursts (GRBs), electromagnetically the most luminous events in the Universe, are short and intense flashes of cosmic high energy (about 10 keV to GeV) photons. The study of GRBs was revolutionized in 1997 when the Italian-Dutch X-ray satellite BeppoSAX started providing the positions of some GRBs with an accuracy of a few arc minutes within a few hours after the burst. This has brought a new dimension to GRB research as multi-wavelength observations of the long-lived emission, known as afterglow of GRB, have provided crucial information about emission mechanisms of GRBs. Optical observations of GRB afterglows have provided valuable information about GRB distances, nature of emission, surroundings, their environments and progenitors. Present status of the possible progenitors of the GRBs shall be reviewed.