  Astrophotonics is the application of photonic technologies to channel,
manipulate, and disperse light from one or more telescopes to achieve
scientific objectives in astronomy in an efficient and cost-effective way.
Utilizing photonic advantage for astronomical spectroscopy is a promising
approach to miniaturizing the next generation of spectrometers for large
telescopes. It can be primarily attained by leveraging the two-dimensional
nature of photonic structures on a chip or a set of fibers, thus reducing the
size of spectroscopic instrumentation to a few centimeters and the weight to a
few hundred grams. A wide variety of astrophotonic spectrometers is currently
being developed, including arrayed waveguide gratings (AWGs), photonic echelle
gratings (PEGs), and Fourier-transform spectrometer (FTS). These astrophotonic
devices are flexible, cheaper to mass produce, easier to control, and much less
susceptible to vibrations and flexure than conventional astronomical
spectrographs. The applications of these spectrographs range from astronomy to
biomedical analysis. This paper provides a brief review of this new class of
astronomical spectrographs.
