From 527810b3b35e663980c135ce58514b3f4faa8422 Mon Sep 17 00:00:00 2001
From: Dinindu Senanayake <dinindusen@gmail.com>
Date: Wed, 31 Jul 2024 08:24:17 +1200
Subject: [PATCH] update the index

---
 docs/index.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/index.md b/docs/index.md
index e1069a0..2669765 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -24,6 +24,7 @@
 
 | **Lesson**                                         | **Overview** | 
 |:---------------------------------------------------|:-------------|
+|Pre . [Unix, Linux and UNIX Shell](./0-unixl-linux-overview.md)|Quick overview on UNIX operating system and it's importance|
 |1. [Introducing the shell](./01-introduction.md)| Introduce `cd` `ls`  |
 |2. [Navigating files and directories](./02-the-filesystem.md)| moving around the filesystem. Introduce absolute vs relative path |
 |3. [Working with files and directories](./03-working-with-files.md)| View, search within, copy, move, and rename files. Create new directories |