The fingerprints of different people and even from the same person differ according to two criteria.  The group the finger belongs to, and the features such as endings and bifurcations of ridges collectively known as minutia points, and the core and delta(s) of the fingerprint .   Fingerprints always have minutiae points, but sometimes lack core and deltas.

The Groups

The group criteria represents a macro vision of the fingerprints, defined by the patterns followed by the finger ridges.  Agora calculates the group of a finger to comply with existing standards, but given current computers' power Agora does not use the group to initially search for a fingerprint.  Agora uses only features thus increasing search and match accuracy.  For more accuracy in some cases Agora uses only minutiae points, and does not use core and deltas.

Arch: The ridges form on one side and tend to go through to the other side of the finger.

Whorl: The ridges tend to present a concentric pattern, spiraled, ovoid or sinusoid.

Right Loops: The ridges flow from the right of the observer, curve at the center of the fingerprint and tend to go back to the same side.

Left Loops: The ridges flow from the left of the observer, curve at the center of the fingerprint and tend to go back to the same side.