The Byurakan-IRAS Galaxy (BIG) sample is the result of optical identifications of IRAS PSC sources at high-galactic latitudes using the First Byurakan Survey (FBS) low-dispersion spectra. Among the 1278 objects most are spiral galaxies and there is a number of ULIRGs among these objects. Our spectroscopic observations carried out with three telescopes (BAO-2.6m, SAO-6m and OHP-1.93m), as well as the SDSS DR8 spectra make up the list of 240 spectroscopically studied BIG objects. All but one have emission lines; we have discovered 70 AGN and composite spectrum objects among them and the others are starbursts. All possible physical characteristics have been measured and/or calculated, including sizes and luminosities. The masses have been estimated based on mass-luminosity relations for spiral galaxies. As it appears, most of these objects are giant massive galaxies. Various multiwavelength (MW) data have been retried from recent catalogs from X-ray to radio and MW SEDs have been built, which have been matched to their optical classifications.