Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS or simply MALDI) has become ubiquitous in the identification and analysis of biomacromolecules. As a technique that allows for the molecular weight determination of otherwise nonvolatile molecules, MALDI has had a profound impact in the molecular biosciences, especially in the field of proteomics. MALDI analysis of whole organisms allows for the generation of a phenotypic profile or "molecular fingerprint;" once established, these fingerprints can be used for identification purposes. (Contains 4 figures and 1 footnote.)