Definition of Fingerprint Region
A spectrum has many regions corresponding to the ranges of certain wavelengths. A Fingerprint region is defined as such a region present in an infrared spectrum which corresponds to 500-1500 cm-1 of wavelength. The fingerprints of humans are different and unique from each other, in the same way, this region of the spectrum is also unique about any given compound.
This region of spectrum constitutes both bending as well as stretching vibrations. It is an immense difficulty to select and pick an individual band and assign them a particular functional group. Such regions are useful in determining and identifying the molecule only if the IR spectrum of that very molecule is already known.