The classes of fingerprints in man are: whorl, arch, loop, and compound. Whorls are spiral patterns with at least two deltas (triangular ridges) and a ridge tracing that makes a complete circuit; arches have a ridgeline that enters from one side of the finger, makes a rise in the center, and exits from the opposite side; loops have ridges that enter from one side, curve around or upward, and exit from the same side they entered; and compound fingerprints have two or more patterns with no single pattern present in 50% or more of the fingerprint. These classes are used in forensic analysis and identification, as each individual has a unique set of fingerprints.