What Is Garbage Collection?

Garbage collection is an automatic memory management process that identifies objects a program no longer references and reclaims their memory, without the developer manually freeing it.

Why it exists

• Manual memory management (like in C) requires the developer to explicitly free memory, which is a common source of bugs — forgetting to free memory (leaks) or freeing it too early (use-after-free)
• Garbage-collected languages remove this manual step by tracking reachability from the program's active state

How to apply it

• An object becomes eligible for collection once nothing in the program can reach it anymore
• Garbage collection removes an entire class of manual memory bugs, but doesn't eliminate memory leaks entirely — objects can still be leaked if something unintentionally keeps a reference to them alive

FAQ

Does garbage collection mean memory leaks are impossible?

No — a "logical" memory leak can still happen if code unintentionally holds a reference to an object (like in a growing cache or an unremoved event listener) that's never actually needed again.