Trace evidence is tiny pieces of evidence or clues that police or detectives use to solve crimes. It can be things like tiny pieces of cloth, hair, and even pieces of food! Detectives collect these tiny bits of evidence and look at them under the microscope to help them figure out how the crime happened. For example, if detectives find a piece of cloth at a crime scene, they might be able to figure out what type of clothing the suspect was wearing. Or if they find a piece of food, they might be able to figure out what kind of food the suspect was eating. Trace evidence is really important because it helps detectives figure out what happened and who was involved in the crime.