Optional chaining ?. is a feature in JavaScript that allows you to safely access deeply nested properties of an object without having to explicitly check if each reference in the chain is valid.

It prevents runtime errors caused by accessing properties of null or undefined.

Use ?. to access a property only if the preceding object is not null or undefined.

Before optional chaining, developers had to use logical AND (&&) checks to access nested properties.

You can use optional chaining to safely access elements of an array that might be null or undefined.

If a method or function might not exist, use optional chaining before calling it.