By A Web Design
The Menu Manager controls how Joomla's menus will look and act.
You can access Menu Manager from the control panel of Joomla admin panel or from the menu Menus -> Menu Manager as shown in Diagram 1.
Or, you can directly click on the desired menu highlighted in yellow color to view the Menu Item Manager.

Diagram 1
The Menu Manager screen opens which lists all the menus in Joomla1.5 as shown in Diagram 2.
Here, you can create menus, edit, copy and delete the menu by clicking on the icon’s at the top-right hand corner.
Click on the Menu Items icon to view the items included in the particular menu. For e.g Click on the Main Menu’s menu item(s) icon.

Diagram 2
The Menu Item Manager of the menu opens which lists the different menu item.
Now, for creating the menu click on the New icon at the top-right hand corner as shown in Diagram 3.
For e.g If you want a new menu item in the main menu, select the mainmenu radio button and click on New.

Diagram 3
You will see the hierarchical structure of Menu Item Type as shown in Diagram 4.
The Menu Item Type determines the type of page that will display when this menu choice is selected by the User.
They are organized into four groups: Internal Link, External Link, Separator, and Alias

Diagram 4
Now, select the Menu Item Type for the new Menu Item being created.
The new Menu item was needed for an article that had to be displayed on the website.
Hence, from the Internal Link select the Articles link, the structure expands and you will see different Layouts for Articles as shown in Diagram 5:

Diagram 5
The description of each of these layouts is given in the following Lessons..