  The innermost regions of Active Galactic Nuclei (AGN) are critical for
understanding galaxy evolution and the dynamics of matter near a Supermassive
Black Hole (SMBH). Yet, due to smaller angular projections, it is very
difficult to resolve these regions. This thesis explores indirect methods to
understand these objects. We use the reverberation mapping technique to
estimate accretion disk sizes for a sample of AGN, finding that the computed
disk sizes are, on average, 3.9 times larger than the Shakura Sunyev (SS)
standard disk model predictions. We also find a weak correlation between the
obtained accretion disk sizes and the SMBH mass. We present initial results
from a new accretion disk monitoring program to probe the accretion disk
structure of Super Eddington Accreting AGN. We report that the disk sizes are
about 4 times larger than the SS disk model. We calibrate the narrow-band
photometric reverberation mapping (PRM) technique to develop tools for a large
systematic narrow-band PRM project. We use simulations to test the effect of
cadence, variability of the light curves, and the length of light curves in
recovering the reverberation lags. We study the dichotomy between AGNs with and
without detected jets using the method of microvariability observed in the
accretion disk continuum. We find that AGNs with confirmed jets are about 3
times more variable on short time scales than the AGNs without a confirmed jet.
By performing statistical analysis on a large sample of low luminosity AGNs, we
find that the NLSy1 galaxies are more likely to have outflow signatures than
their broad-line counterparts, hinting toward the disk wind origin of the
material in BLR. We find that the principal components for NLSy1 galaxies
differ from the BLSy1 galaxies, suggesting that the NLSy1 galaxies could be
occupying their own parameter space.
