diff --git a/courses/linux_basics/command_line_basics.md b/courses/linux_basics/command_line_basics.md
index f5a17a0..04b151c 100644
--- a/courses/linux_basics/command_line_basics.md
+++ b/courses/linux_basics/command_line_basics.md
@@ -326,11 +326,14 @@ More command displays the contents of a file or a command output,
 displaying one screen at a time in case the file is large (Eg: log files).
 It also allows forward navigation and limited backward navigation in the file.
 
+![](images/linux/commands/image33.png)
+
+More command displays as much as can fit on the current screen and waits for user input to advance. Forward navigation can be done by pressing Enter, which advances the output by one line and Space, which advances the output by one screen.
 
 ### less
 
 Less command is an improved version of more. It displays the contents of a file or a command output, one page at a time.
-It allows backward navigation as well as forward navigation in the file and also has search options. 
+It allows backward navigation as well as forward navigation in the file and also has search options. We can use arrow keys for advancing backward or forward by one line. For moving forward by one page, press Enter and for moving backward by one page, press b on your keyboard.
 You can go to the beginning and the end of a file instantly.
 
 
diff --git a/courses/linux_basics/images/linux/commands/image33.png b/courses/linux_basics/images/linux/commands/image33.png
new file mode 100644
index 0000000..3fafb44
Binary files /dev/null and b/courses/linux_basics/images/linux/commands/image33.png differ
diff --git a/courses/linux_basics/intro.md b/courses/linux_basics/intro.md
index d195ef0..8c3b3d9 100644
--- a/courses/linux_basics/intro.md
+++ b/courses/linux_basics/intro.md
@@ -79,6 +79,9 @@ and system utilities. The Linux kernel was independently developed and
 released by Linus Torvalds. The Linux kernel is free and open-source -
 [https://github.com/torvalds/linux](https://github.com/torvalds/linux)
 
+Linux is a kernel and and not a complete operating system. Linux kernel is combined with GNU system to make a complete operating system. Therefore, linux based operating systems are also called as GNU/Linux systems. GNU is an extensive collection of free softwares like compiler, debugger, C library etc.
+[Linux and the GNU  System](https://www.gnu.org/gnu/linux-and-gnu.en.html)
+
 History of Linux -
 [https://en.wikipedia.org/wiki/History_of_Linux](https://en.wikipedia.org/wiki/History_of_Linux)