docs: Add localStorage example (#10973)

docs/runtime/web_storage_api.md

@@ -7,3 +7,33 @@ introduced, which through `localStorage` allows persistent storage, whereas
 To use persistent storage, you need to pass the `--location` flag. The location
 for persistent storage is listed in `deno info`, and additionally passing the
 `--location` will give you the path for the specified origin.
+
+To learn more about the Web Storage APIs, visit the
+[MDN page on Web Storage](https://developer.mozilla.org/en-US/docs/Web/API/Storage).
+
+### Example
+
+The following snippet accesses the local storage bucket for the current origin
+and adds a data item to it using `setItem()`.
+
+```ts
+localStorage.setItem("myDemo", "Deno App");
+```
+
+The syntax for reading the localStorage item is as follows:
+
+```ts
+const cat = localStorage.getItem("myDemo");
+```
+
+The syntax for removing the localStorage item is as follows:
+
+```ts
+localStorage.removeItem("myDemo");
+```
+
+The syntax for removing all the localStorage items is as follows:
+
+```ts
+localStorage.clear();
+```