JavaScript type Overview

 

This figure is from Chapter 3 P184 of JavaScript language essence and programming practice. I recently changed the second version. This figure has been redone. You can check the figure as needed.

In addition, the following concepts are added:

1. The difference between a built-in (Build-in) object and a native (Naitve) object is that the former is always an object created during the engine initialization phase and is a subset of the latter; the latter includes some objects dynamically created during the running process.

2. Engine extension objects are not very large sets. Generally, they are also native objects of the engine (but not ECMA-compliant native objects ).

3. The host object is not the native object of the engine. Instead, the host framework registers the object in the JavaScript engine through a mechanism.

4. Some hosts call their own object/constructor "Native object". For example, Internet Explorer 7 calls its XMLHttpRequest () it is called Native. In contrast, in earlier versions, new ActiveXObject ('Microsoft. XMLHTTP. In this case, the reader should note the difference between "Native objects of the Host" and "Native objects of the engine ".

From lovedreamland's blog