We present a catalog of 9316 spectroscopically confirmed white dwarfsfrom the Sloan Digital Sky Survey Data Release 4. We have selected thestars through photometric cuts and spectroscopic modeling, backed up bya set of visual inspections. About 6000 of the stars are newdiscoveries, roughly doubling the number of spectroscopically confirmedwhite dwarfs. We analyze the stars by performing temperature and surfacegravity fits to grids of pure hydrogen and helium atmospheres. Among therare outliers are a set of presumed helium-core DA white dwarfs withestimated masses below 0.3 Msolar, including two candidatesthat may be the lowest-mass yet found. We also present a list of 928 hotsubdwarfs.