This book is based on my research of the lock and key system and how it has developed through time. My research process started by identifying the beginning of the idea of protection and how it led to the invention of keys. I also inspect what we, as humans, want to protect has changed over the centuries. Human's started by protecting our homes and belongings to now to securing our phones and computers. I found the the modern day lock mechanism has been used for centuries and is now just recently starting to advance into biometric locks, which are now being used in modern technology. From there I explored how biometric locks are becoming the standard. My research concluded by theorizing that biometric locks show how humans themselves are becoming keys, and exploring paths this could take in the future.