First row, left: spectrum of the highest redshift quasar (z = 5.855) observed by BOSS; this quasar was discovered by Fan et al. (2004); the quasar with highest redshift discovered by BOSS is SDSS J222018.50−010147.0 at z = 5.605. First row, right: spectrum of the most luminous (M_i[z = 2] = −30.91) quasar available in this catalog. Middle and bottom rows: four typical quasar spectra selected to be representative in terms of S/N at different redshifts (z ~ 2.3, 2.5, 2.7, 3.5). The S/N listed is the median S/N per pixel over the whole spectrum. All the spectra were boxcar median smoothed over 5 pixels.