1. A method comprising: receiving spectral information for multiple reference samples using a spectral data processor, each reference sample associated with a different material and comprising a plurality of peak wavelengths distributed across a spectrum that identifies the material; producing peak and bin information that comprises the spectrum partitioned into multiple different sized range bins using a distribution of combined peak wavelengths compressed from the spectral information of the multiple reference samples across the spectrum, each range bin comprising a substantially equal number of the combined peak wavelengths and at least one peak wavelength from two or more of the reference samples, wherein the peak and bin information is produced by the spectral data processor and the peak and bin information also comprises a signature for each reference sample that includes an indication for each of the range bins that corresponds to the presence or absence of a peak wavelength for the reference sample; storing the peak and bin information for the reference samples on a handheld device comprising a memory and a processing resource that performs a method comprising: analyzing an unknown sample to produce spectral information from the unknown sample; indexing a plurality of peak wavelengths in the spectral information from the unknown sample to the range bins in the partitioned spectrum to produce a signature of the unknown sample that includes an indication for each of the range bins that corresponds to the presence or absence of a peak wavelength from the unknown sample; generating probability information that identifies the spectral information of a reference sample as a best match to the spectral information of the unknown sample by comparing the signature of the unknown sample to the signature of each reference sample; and notifying a user of the material associated with the reference sample that is a best match to the unknown sample to a user via a display screen on the handheld device.