In ECMAScript, how are some of native objects also built-in?
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Good morning! I suppose a definition of native and built-in objects is required to answer this question. Here's what the ECMAScript spec defines these as:

> 4.3.6 native object
>
> object in an ECMAScript implementation, independent of the host environment, that is present at the start of
> the execution of an ECMAScript program.
> 
> NOTE   Standard native built-in objects are defined in this
> specification. **Some native objects are built-in**; others may be
> constructed ruing the course of execution of an ECMAScript program
> 
> 4.3.7 built-in object 
>
> object supplied by an ECMAScript implementation, independent of the host environment, that is present
> at the start of the execution of an ECMAScript program
> 
> NOTE   Standard built-in objects are defined in this specification,
> and an ECMAScript implementation may specify and define others. Every
> built-in object is a native object. A *built-in constructor* is a
> built-in object that is also a constructor.

I'm looking forward to an explanation of this one. so hopefully someone can help!
