Annu. Rev. Astron. Astrophys. 2000. 38: 667-715 Copyright © 2000 by Annual Reviews. All rights reserved

1.1. This Review

The Hubble deep fields north and south (HDF-N and HDF-S, respectively) are by now undoubtedly among the most "data rich" portions of the celestial sphere. The task of reviewing progress is complicated by the fact that much of the supporting data are still being gathered, and by the wide range of uses that have been found for the HDF. It is not practical to provide a comprehensive review of all HDF-related research in a single review article. Instead we have chosen to divide the review into two parts. The first part discusses the data, both from HST and from other facilities, and summarizes measurements and phenomenology of the sources found in the field. The second part focuses specifically on distant galaxies, and attempts to provide a critical view of what the HDF has, and has not, taught us about galaxy evolution. [Ferguson 1998a] has reviewed the HDF with a different focus, and the series of papers in the 1996 Herstmonceux conference and the 1997 STScI May Symposium provide a broad summary of the overall field [Tanvir et al. 1996, Livio et al. 1997]. Throughout this review, unless explicitly stated otherwise, we adopt cosmological parameters _M, , _tot = 0.3, 0.7, 1.0 and H₀ = 65 km s^-1 Mpc^-1. Where catalog numbers of galaxies are mentioned, they refer to those in [Williams et al. 1996].