We leave small traces of ourselves everywhere we go. By definition of Locard’s Principle, every time you come into contact with another person, place, or thing, it results in an exchange of physical materials. These forensic footprints can be literally anything that makes you who you are.
THE PATTERNS IN OUR PRINTS
A fingerprint is one example of something that can be left behind. There are three main types of fingerprint patterns called arches, loops, and whorls. These categories can further be classified into more complex structures and patterns.
No two fingerprints are the same. Everyone has a fingerprint that is unique to themselves. This is because of the major features of a fingerprint, called minutiae. There are many different shapes of minutiae.
The placement of minutiae on a fingerprint can show up in different combinations. According to the 12-point match rule, twelve or more minutiae points are needed to declare a fingerprint match.
Fingerprints that are created by the natural oils that reside on a person’s fingertips are called latent fingerprints. Most types of fingerprints are not usually detectable to the naked eye. However, in some cases, a fingerprint can be noticeable on a surface.
A person can actually lose or alter their fingerprint if their fingertips have been through some trauma. A cut or burn can scar the fingertip and make it unnoticeable. Also, with age, a person’s fingerprints tend to stretch and change.
A HAIRY SITUATION
Hair follicles are another example of something that can be left behind. It’s normal for a person to shed between 50 and 100 hairs a day.
A hair follicle is made up of a root and a shaft. The shaft is further comprised of three layers. The medulla is the innermost layer of the hair shaft. The cortex is the middle layer of the hair shaft. The cuticle is the outermost layer of the hair shaft.
. 
If the hair follicle has any skin cells still attached to the root, then it also contains the DNA of the person who left it. Otherwise, hairs, in general, are very similar.
