  We try to understand the quasi-periodic oscillations (QPOs) in low-mass
neutron-star and black-hole X-ray binaries by a resonance model in warped disks
with precession. Our main concern is high-frequency QPOs, hectohertz QPOs, and
horizontal-branch QPOs in the z sources and the atoll sources, and the
correponding QPOs in black-hole X-ray binaries. Our resonance model can
qualitatively, but systematically, explain these QPOs by regarding hectohertz
QPOs as a precession of warp.
