  A field theory of quantum Hall effects is constructed based on the \CB
picture. It is tightly related with the microscopic wave-function theory. The
characteristic feature is that the field operator describes solely the physical
degrees of freedom representing the deviation from the Laughlin state. It
presents a powerful tool to analyze excited states within the \LLL. It is shown
that all excitations are nonlocal topological solitons in the spinless quantum
Hall system. On the other hand, in the presence of the spin degree of freedom
it is shown that a quantum coherence develops spontaneously, where excitations
include a Goldstone mode besides nonlocal topological solitons. Solitons are
vortices and Skyrmions carrying the U(1) and SU(2) topological charges,
respectively. Their classical configurations are derived from their microscopic
wave functions. The Skyrmion appears merely as a low-energy excitation within
the \LLL and not as a solution of the effective nonlinear sigma model. We use
it as a consistency check of the Skyrmion theory that the Skyrmion is reduced
to the vortex in the vanishing limit of the Skyrmion size. We evaluate the
activation energy of one Skyrmion and compare it with experimental data.
