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Prototypes
hardComplete guide with examples and interview questions · 35 min
Definition
Say it out loud in an interview — clear, simple, no textbook wording.
JavaScript uses prototypal inheritance: objects delegate property lookups to another object via an internal link. There is no classical copying of class blueprints — objects link to shared prototypes.
Quick Stats
35
Minutes
hard
Difficulty
4
Interview Q's
Key takeaways
- •Every object has an internal prototype link used for property lookup
- •The prototype chain ends at null
- •Constructor functions set prototype on new instances
- •Classes are syntactic sugar over constructor plus prototype
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