diff --git a/src/content/9/en/part9c.md b/src/content/9/en/part9c.md
index 82b35715fcb..b92994a214f 100644
--- a/src/content/9/en/part9c.md
+++ b/src/content/9/en/part9c.md
@@ -603,6 +603,57 @@ export interface DiaryEntry {
}
```
+### Node and JSON modules
+
+It is important to take note of a problem that may arise when using the tsconfig [resolveJsonModule](https://www.typescriptlang.org/en/tsconfig#resolveJsonModule) option:
+
+```json
+{
+ "compilerOptions": {
+ // ...
+ "resolveJsonModule": true // highlight-line
+ }
+}
+```
+
+According to the node documentation for [file modules](https://nodejs.org/api/modules.html#modules_file_modules),
+node will try to resolve modules in order of extensions:
+
+```sh
+ ["js", "json", "node"]
+```
+
+In addition to that, by default, ts-node and ts-node-dev extend the list of possible node module extensions to:
+
+```sh
+ ["js", "json", "node", "ts", "tsx"]
+```
+
+> **NB**: The validity of .js, .json and .node files as modules in Typescript depend on environment configuration, including tsconfig options such as allowJs and resolveJsonModule.
+
+Consider a flat folder structure containing files:
+
+```sh
+ ├── myModule.json
+ └── myModule.ts
+```
+
+In typescript, with the resolveJsonModule option set to true, the file myModule.json becomes a valid node module. Now, imagine a scenario where we wish to take the file myModule.ts into use:
+
+```js
+import myModule from "./myModule";
+```
+
+Looking closely at the order of node module extensions:
+
+```sh
+ ["js", "json", "node", "ts", "tsx"]
+```
+
+We notice that the .json file extension takes precedence over .ts and so myModule.json will be imported and not myModule.ts.
+
+In order to avoid time eating bugs, it is recommended that within a flat directory, each file with a valid node module extension has a unique filename.
+
### Utility Types