  The present common view about GRB origin is related to cosmology, what is
based on statistical analysis, and on measurements of the redshifts in the GRB
optical afterglows of long GRB. Models of radiation, and models of the central
machine for GRB are critically analyzed. Most of these models cannot produce
the amount of energy required for the cosmological GRB. Collimation is needed
to reduce GRB energy output. No correlation is found between redshifts, GRB
spectrum, and total GRB fluence. Comparison of KONUS and BATSE data about
statistics and hard X-ray lines is done, and some differences are noted. Hard
gamma-ray afterglows, prompt optical spectra, hard X-ray lines measurements
could be important for farther insight into GRB origin. Two bright optical
afterglows had been detected, indicating that initial bright optical emission
is directly connected with the GRB itself, and has a different origin from the
subsequent faint optical emission. Results of these observations are
represented. Observations indicate that GRB originate in star forming regions
of galaxies with a high matter density. Interaction of the mighty gamma ray
flux from the cosmological GRB with the dense surrounding molecular cloud lead
to long optical afterglow, lasting up to 10 years, due to reradiation of the
cloud. Results of numerical simulations of such reradiation for different forms
of clouds are represented. Possible connection of short GRB with soft gamma
repeaters is discussed.
