add faq for user's private home directory

docs/faq.md

@@ -1 +1,24 @@
 # Frequently Asked Questions
+
+Q1: Can a user access another user's home directory in JupyterLab?
+
+No. Every user's home directory is private to themselves and they cannot access contents
+of any other user's home directory. Example below shows the permissions of user directories
+in `/home`.
+
+```bash
+$ ls -ltrh /home
+
+total 36K
+drwx------  9 john-doe       example-user 4.0K Apr  1 19:22 john-doe
+drwx------  9 alice-doe      example-user 4.0K Apr  1 19:34 alice-doe
+```
+
+```bash
+john-doe@worker-01:~$ pwd
+/home/john-doe
+
+# The user john-doe unable to access contents of user alice-doe's home directory:
+john-doer@worker-01:~$ ls /home/alice-doe/
+ls: cannot open directory '/home/alice-doe/': Permission denied
+```