Locard's exchange principle
Imagine you're at a playground and decide to play with your friend's toy. You touch the toy, and your friend touches it, too. Later, your friend's mom comes to pick them up, and you both leave the playground. When your friend gets home, their mom notices that their toy is missing.
This is where Locard's exchange principle comes in. When two objects come into contact, they can transfer materials between them. So when you touched your friend's toy, you left behind some of your skin cells and maybe some dirt that was on your hands. And when your friend touched the toy, they left behind their own skin cells and maybe some oil from their skin.
When the mom realizes the toy is missing, they might check for fingerprints on the toy. This is because the oils and other materials on our fingers can also be transferred to objects we touch, and those can make fingerprints that detectives can use to try and identify who touched the toy last.
So, in summary, Locard's exchange principle is the idea that objects can transfer materials when they touch each other, and those materials can help people figure out who touched or interacted with the objects.
This is where Locard's exchange principle comes in. When two objects come into contact, they can transfer materials between them. So when you touched your friend's toy, you left behind some of your skin cells and maybe some dirt that was on your hands. And when your friend touched the toy, they left behind their own skin cells and maybe some oil from their skin.
When the mom realizes the toy is missing, they might check for fingerprints on the toy. This is because the oils and other materials on our fingers can also be transferred to objects we touch, and those can make fingerprints that detectives can use to try and identify who touched the toy last.
So, in summary, Locard's exchange principle is the idea that objects can transfer materials when they touch each other, and those materials can help people figure out who touched or interacted with the objects.