Dynamics of The Tranquil Cosmic Web

The phase space distribution of matter out to $\sim 100\mathrm{M}\mathrm{p}\mathrm{c}$ is probed by two types of observational data: galaxy redshift surveys and peculiar motions of galaxies. Important information on the process of structure formation and deviations from standard gravity have been extracted from the accumulating data. The remarkably simple Zel’dovich approximation is the basis for much of our insight into the dynamics of structure formation and the development of data analyses methods. Progress in the methodology and some recent results is reviewed.