From c1333ea1131dec744193679b7e5cf6d2f59456ca Mon Sep 17 00:00:00 2001
From: Harshitha KP <harshi46@in.ibm.com>
Date: Mon, 6 Jan 2020 00:52:14 -0500
Subject: [PATCH] doc: explain native external types

There is a reference to native external types in
util.types.isExternal api documentation. Provide
a brief explanation to that.
Refs: https://github.com/nodejs/node/pull/31173#discussion_r362816411

PR-URL: https://github.com/nodejs/node/pull/31214
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
---
 doc/api/util.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/doc/api/util.md b/doc/api/util.md
index 6a6eaf65e7ef50..469bcf2b6455e9 100644
--- a/doc/api/util.md
+++ b/doc/api/util.md
@@ -1392,6 +1392,11 @@ added: v10.0.0
 * Returns: {boolean}
 
 Returns `true` if the value is a native `External` value.
+A native `External` value is a special type of object whose
+data is not stored within the JavaScript managed heap
+and does not conform to standard JavaScript types. Such
+objects are created either by Node.js internals or native
+addons and are wrapped by a JavaScript object.
 
 ### `util.types.isFloat32Array(value)`
 <!-- YAML