Null

overview

Remember these Terms

• Null: intentional absence of any value.
• Undefined: variable declared but not assigned.
• Falsy: values that behave like false (0, "", null, undefined, NaN).
• Truthy: any value that behaves like true.
• Type coercion: automatic conversion between types.
• Equality (==): compares after coercion.
• Strict equality (===): compares without coercion.
• Nullish coalescing (??): use a default only for null/undefined.
• Optional chaining (?.): safely read nested properties.
• Default parameter: fallback value when argument is missing.