One of the ways astronomers study the universe is by examining and analyzing the electromagnetic radiation generated by objects within it. A Spectrometer is a backend instrument used to process (separate) all wavelengths of electromagnetic radiation signals into different frequencies and bandwidths. In short, it's designed to produce spectra for further manipulation and analysis by a computer. Through spectroscopy, the study of spectra, astronomers can analyze the composition of planets, dust clouds, galaxies, and other astronomical features, thereby determining their chemical and molecular makeup. The spectroscopic study of stars and galaxies has produced a wealth of valuable knowledge as these objects provide laboratories where conditions unattainable on earth are maintained. These conditions include extremely high temperatures and extremely high and low pressure for example. We can also determine with relative accuracy, the motions of celestial objects through spectral analysis. By examining shifts in the position of spectral lines (shifts in wavelength i.e., the Doppler effect), a fairly accurate value for the relative speed and direction (towards or away from earth) of any source of radiation can be calculated. Studying the Doppler shifts observed in the spectra of exterior galaxies for example has indicated that our universe is expanding. The GBT Spectrometer, a large-scale correlator designed by Ray Escoffier at the NRAO's Central Development Lab, was developed to support research in spectroscopy as well as other fields. Spectral line, continuum and pulsar observing and analysis are prime areas the Spectrometer was designed to exploit. In the paragraphs that follow, bracketed numbers are included to reference related source documentation. Please see the paragraph on technical references for further details.