JavaScript Optional_chaining Guide
Optional chaining (?.) safely accesses nested object properties without throwing on null/undefined. The guide walks through ?. Operator. `obj?.prop` — undefined if obj is null/undefined. `obj?.[expr]` — computed access. `obj.fn?.()` — call only if exists. Short-circuits: stops evaluating after first missing property. `const city = user?.address?.city`. Safer than `&&` chaining. The guide is organized into 1 sections that build on each other, each pairing a prose explanation with runnable code. Related guides: Arrays, Strings, Numbers, Math, Date. This is one of 145 JavaScript guides on JS Reference — see the full list on the guides page. Practice what you learn in the JavaScript playground, and look up any unfamiliar term in the JavaScript glossary.