  We present stellar variability towards the young open cluster NGC\,6823. Time
series $V$- and $I$-band CCD photometry led to identification and
characterization of 88 variable stars, of which only 14 have been previously
recognized. We ascertain the membership of each variable with optical $UBVI$
and infrared photometry, and with Gaia EDR3 parallax and proper motion data.
Seventy two variable stars are found to be cluster members, of which 25 are
main sequence stars and 48 are pre-main-sequence stars. The probable cluster
members collectively suggest an isochrone age of the cluster to be about 2~Myrs
based on the GAIA photometry. With the color and magnitude, as well as the
shape of the light curve, we have classified the main sequence variables into
$\beta$~Cep, $\delta$~Scuti, slowly pulsating B type, and new class variables.
Among the pre-main-sequence variables, eight are classical T Tauri variables,
and four are Herbig Ae/Be objects, whereas the remaining belong to the
weak-lined T Tauri population. The variable nature of 32 stars is validated
with TESS light curves. Our work provides refined classification of variability
of pre-main-sequence and main-sequence cluster members of the active
star-forming complex, Sharpless\,86. Despite no strong evidence of the
disk-locking mechanism in the present sample of TTSs, one TTS with larger
$\Delta(I-K)$ is found to be slow rotator.
