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Objects
mediumComplete guide with examples and interview questions · 30 min
Definition
Say it out loud in an interview — clear, simple, no textbook wording.
An object is a collection of properties — keys mapped to values. Arrays and functions are objects too, but plain objects {} are the workhorse for structured data.
Objects are reference types: variables hold pointers, not the object itself.
Quick Stats
30
Minutes
medium
Difficulty
4
Interview Q's
Key takeaways
- •Objects store keyed properties; keys are coerced to strings
- •Reference equality means two literals are never === unless same reference
- •Shallow copy spreads one level only
- •Optional chaining and nullish coalescing prevent common access errors
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