Dramas like Silent Witness have hooked millions of us on the world of forensic science, but the jargon can be a bit baffling. Keep one step ahead with our handy guide.
1: Blood spatter
When blood is spilled during a crime, the patterns it leaves on surfaces can offer invaluable information to forensic scientists. Depending on the pattern, the blood spatter can reveal the type of weapon that caused it, the size of the wound, and precisely how the victim was positioned when the attack took place.
2: Chain of custody
Every stage in the storage of evidence must be documented, from who discovers it, to who it's then handed to and who runs tests on it. Each link in this chain of custody is recorded to ensure the evidence isn't tampered with. If any phase is unaccounted for, the evidence may be inadmissible in court.
3: Cold hit
If DNA evidence is found at the crime scene, police will look through the genetic records of known offenders to find a DNA match. A match would strongly indicate that the same person is responsible for the new case. This is known as a cold hit.
4: Crime scene staging
A criminal may attempt to alter the crime scene in a bid to mislead forensic experts. They may leave a false weapon as a red herring, or they may attempt to hide signs of a struggle in the room. This is called crime scene staging.
5: Grave wax
This is a crumbly, white substance that forms on the face, breasts and buttocks of a corpse. The result of a breakdown in body fat, it can indicate how long ago the murder occurred. As it's particularly pronounced in moist conditions, it can also indicate where the crime took place.
6: Petechial marks
In cases of death-by-strangulation, bodies will commonly exhibit petechial marks. These are red dots that appear on the skin, often on the eyelids. Their presence almost certainly proves that foul play has occurred.
7: Ridge characteristics
When experts compare the fingerprints found at a crime scene with those of a suspect, they search for any matching patterns within the loops and whorls of each print. These ridge characteristics must be identical to prove the suspect is the culprit.
8: Trace evidence
This is evidence that can only be found through close analysis of every inch of the crime scene. Hairs, fibres and latent fingerprints (prints not visible to the naked eye) are the most common.