Light can carry spin angular momentum and orbital angular momentum. The spin angular momentum is associated with the circular polarization state of the beam, while the orbital angular momentum is related to the spiral phase of the beam. Since Allen et al. theoretically confirmed the physical concept of the orbital angular momentum of photons in 1992, this novel type of light field with a special spiral phase wavefront has attracted many research interests and found many important applications in both classical and quantum optical realms. This study, from both the fundamental and applied physics, reviews the preparation and detection methods of the orbital angular momentum beam, especially the recent progress in a variety of fields with the orbital angular momentum ranging from spiral-phase contrast imaging and remote sensing of the rotational Doppler effect to optical micromanipulation.