Glossary term
What is memory leak? Meaning for developers
In Scenario Debugging
Memory that is no longer needed but is still referenced. The garbage collector (the memory cleaner) cannot free it.
Learn it properly · Scenario DebuggingLesson 4: Memory Leaks in Single-Page AppsTimers and listeners that are never cleared, detached DOM nodes, closures that hold big objects and caches that only grow. Also how to confirm a leak with heap snapshots.In JavaScript Part 2
Memory you no longer need but still hold a reference to, so it is never freed.
Learn it properly · JavaScript Part 2Lesson 7: Memory, Garbage Collection and WeakMap/WeakRefReachability, five usual leaks measured, WeakMap and WeakRef, typed arrays and how to find a leak with heap snapshots.In Node.js From Zero
Memory that is still reachable but no longer needed, so it grows over time and the garbage collector cannot free it.
Learn it properly · Node.js From ZeroLesson 8: Testing, Performance and Production Habitsnode:test, profiling with --cpu-prof, memory leaks, configuration, Docker basics, and a production checklist.