Children learn the concept of ownership quickly. Many a toddler's first word is "mine!"
And there are plenty of places where ownership is clear, like when your name appears on the deed to your house. It's less clear in areas like the zone behind your airplane seat, or who owns your data online, or whether your friends can borrow your Netflix password.
Michael Heller and James Salzman give examples like these and more in the book Mine! How the Hidden Rules of Ownership Control Our Lives. The authors drop by to help us understand where our ownership ends, and someone else's begins.