  We study an open cluster NGC 6940 using \textit{AstroSat}/UVIT data and other
archival data. This is an intermediate age cluster ($\sim$ 1 Gyr), located at
about 770 pc distance, harboring several exotic populations apart from normal
single and binary stars. We identify members of this cluster using a machine
learning algorithm, ML-MOC and identify 492 members, including 1 blue straggler
star (BSS), 2 yellow straggler stars (YSS), 11 blue lurker (BL) candidates, and
2 red clump (RC) stars. The cluster shows the effect of mass segregation, with
massive stars segregated the most into the cluster, followed by the equal-mass
binary members and the single low mass stars. We report the presence of an
extended main-sequence turn-off (eMSTO) feature in this cluster and suggest
that the age spread may be a contributing factor behind it. However, the effect
of stellar rotation, and the dust absorption needs to be examined more
comprehensively with a larger fraction of MSTO stars. All the sixteen sources
mentioned above have a counterpart in the UVIT/F169M filter. In order to
characterize them, we construct multi-wavelength spectral energy distributions
(SEDs) of 14 of these objects having no nearby sources within 3". The BSS is
successfully fitted with a single-component SED. We find that three BLs, two
YSS, and one RC star have UV excess greater than 50$\%$ and successfully fit
two-component SEDs having hot companions. The parameters derived from the SEDs
imply that the hot companions of BLs and the RC star are low-mass and
normal-mass white dwarfs, whereas the hot companions of YSS are likely to be
subdwarf B (sdB) stars. We suggest that at least 6 out of 14 stars ($\sim$42
$\%$) are formed via mass transfer and/or merger pathways.
