"An object is a member of Object" in ES2017 Specs

Question

Can anyone help explain "An object is a member of Object" in ES2017 Language Specs? The sentence shows up in the specs multiple times. For example, in Chapter 4.2 ECMAScript Overview

Properties are containers that hold other objects, primitive values, or functions. A primitive value is a member of one of the following built-in types: Undefined, Null, Boolean, Number, String, and Symbol; an object is a member of the built-in type Object; and a function is a callable object. A function that is associated with an object via a property is called a method.

Answer 1

Javascript is a language made up of objects. object({}) is not the only type of Object. Arrays, functions, maps are all type of Object, expect for the primitives mentioned in the spec all are type of Object. The term

an object is a member of the built-in type Object

means that regular object({}) is part of the primitive built in type Object (notice the difference in caps and smalls). you can continue to say

function is a member of the built-in type Object, Array is part of and so on..

Answer 2

It's a specification. It defines things like these, and states that EcmaScript uses different types, "sets of data values" if you want. Then it goes on to define that

• we call one of these types the Object type (notice the capital O - it's always used when referring to the type and not the ordinary term "object" or the Object constructor function)
• we call the members of this particular type objects.