New one-dimensional spectral classifications for 90 Galactic globular clusters and NGC 121 in the Small Magellanic Cloud are extensively compared with previous classifications, photometric and spectroscopic metallicity indicators, horizontal-and giant-branch morphological descriptors, spatial distribution parameters, and reddening, in what amounts to a review of the Galactic globular clusters from the view point of spectral classifications of their integrated light. The homogeneous data base

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... sists of -260 image-tube spectra at 120 A mm -1 . Twenty-three clusters, many of them lying in the direction of the Galactic nuclear bulge, have been classified for the first time. We find that large uncertainties in (B-V) and E(B~V) cause Kukarkin's (1974) photometrically estimated spectral types to scatter widely about ours and we recommend discontinuation of the use of them or of metallicities inferred from them. Our types correlate tightly with Harris and Ganterna s (1977) Ç) C mt> Zinn's (1980«) Ç) 39 , and Burstein et al.'s (1984) Mg 2 photometric indices, but greater scatter is seen in plots against (B -V) 0 from Harris and Racine's (1979) tabulation or C (42-45) 0 from Bica and Pastoriza's (1983) DDO photometry. Ultraviolet CN band strength becomes noticeable in our spectra near type F7-F8 and increases steadily, but with considerable scatter, as spectral type increases. Cautionary remarks about the traditional interpretation of CN as a luminosity indicator in old stellar populations are also made. Tight correlations between our types and most metallicity determinations mirror the present uncertainties in the abundance scale for the metal-rich globular clusters. Linear correlations are found between spectral type and metallicities based on the scale where 47 Tue and M71 have 0.7 < [Fe/H] :S -0.5, while nonlinear relations exist if those clusters have [Fe/H] --1.1. Second-parameter effects (arising from the distribution of stars on the horizontal branch) do not seem to dominate our classifications. Extensive tables are given that summarize a number of spectral classifications, photometric indices, metallicity values, etc. for the Galactic globular clusters. Appendices provide detailed notes on individual clusters, and descriptions of those spectra in which emission lines were detected.