Object Pool
In plain terms
Reusing a set of pre-created objects instead of recreating them.
Going deeper
The Object Pool pattern keeps a pool of reusable objects to avoid the cost of frequent creation and destruction. Objects are borrowed and returned.
Under the hood
Worth it when object creation is expensive (connections, threads); requires careful state reset on return.
Examples
Connection pools, thread pools, game-object reuse, expensive-object management.
Think of it like...
Like a tool library you borrow from and return to, rather than buying tools each time.