  The first X-ray source catalog of Insight-HXMT Galactic Plane (|b|<10deg)
Scanning Survey (GPSS) is presented based on the data accumulated from June
2017 to August 2021. The 4 yr limit sensitivities at main energy bands can
reach 8.2x10^(-12) erg/s/cm^2} (2-6 keV), 4.21x10^(-11) erg/s/cm^2 (7-40 keV)
and 2.78x10^(-11) erg/s/cm^2 (25-100 keV). More than 1300 sources have been
monitored at a wide band (1$-$100\,keV), of which 223 sources have a
signal-to-noise ratio greater than 5. We combined the GPSS data of Insight-HXMT
and MAXI and found it is feasible to obtain more complete long-term light
curves from their scanning results. The flux variabilities at different energy
bands of the 223 bright sources are analyzed based on the excess variances. It
is found that the fluxes of X-ray binaries are more active than those of
supernova remnants and isolated pulsars. Different types of binaries, e.g.,
low-mass X-ray binaries (LMXBs), high-mass X-ray binaries (HMXBs), neutron star
binaries, and black hole binaries, also distinctively show different
regularities. In addition, the relations between the hardness ratio (HR) and
excess variances, and HR and source types are analyzed. It is obvious that the
HRs of HMXBs tend to be harder than those of LMXBs and HMXBs tend to be more
active than those of LMXBs.
