  We use helioseismic data from ground and space-based instruments to analyze
how solar rotation has changed since the beginning of solar Cycle 23 with
emphasis on studying the differences between Cycles 23 and 24. We find that the
nature of solar rotation is indeed different for the two cycles. While the
changes in the latitudinally independent component follows solar-cycle indices,
some of the other components have a more complicated behavior. There is a
substantial change in the behavior of the solar zonal flows and their spatial
gradients too. While the zonal flows are in general weaker in Cycle 24 than
those in Cycle 23, there are clear signs of the emergence of Cycle 25. We have
also investigated the properties of the solar tachocline, in particular, its
position, width, and the change (or jump) in the rotation rate across it. We
find significant temporal variation in the change of the rotation rate across
the tachocline. We also find that the changes in solar Cycle 24 were very
different from those of Cycle 23. We do not find any statistically significant
change in the position or the width of the tachocline.
