  We describe the subject of Cosmic Microwave Background (CMB) analysis - its
past, present and future. The theory of Gaussian primary anisotropies, those
arising from linear physics operating in the early Universe, is in reasonably
good shape so the focus has shifted to the statistical pipeline which confronts
the data with the theory: mapping, filtering, comparing, cleaning, compressing,
forecasting, estimating. There have been many algorithmic advances in the
analysis pipeline in recent years, but still more are needed for the forecasts
of high precision cosmic parameter estimation to be realized. For secondary
anisotropies, those arising once nonlinearity develops, the computational state
of the art currently needs effort in all the areas: the Sunyaev-Zeldovich
effect, inhomogeneous reionization, gravitational lensing, the Rees-Sciama
effect, dusty galaxies. We use the Sunyaev-Zeldovich example to illustrate the
issues. The direct interface with observations for these non-Gaussian signals
is much more complex than for Gaussian primary anisotropies, and even more so
for the statistically inhomogeneous Galactic foregrounds. Because all the
signals are superimposed, the separation of components inevitably complicates
primary CMB analyses as well.
