One-way greenhouse gases do not absorb any incoming sunlight, but they do absorb outgoing infrared heat. One-way GhGs include nitrogen, argon, neon, krypton, helium, hydrogen (probably), and xenon.
Two-way greenhouse gases absorb both incoming sunlight and outgoing infrared heat. Two-way GhGs include oxygen, which is by far the chief absorber of harmful ultraviolet (UV) rays, water vapor, carbon dioxide, nitrous oxide, methane and ozone. Atmospheric oxygen (O2) absorbs about 250,000 times more harmful UV rays than its more famous alotrope ozone (O3). The ozone scare was a hoax, as is the current carbon dioxide hoax.