What is a Custom Menu?
Want to have a menu for your site you can actually configure? Rather than using the Pages Widget to create a navigation area now you can create a menu containing page, categories and custom links – ordered however you would like.
Video: Using Custom Menus
You will need to have a left sidebar in your theme for the Custom Menus to work automatically, otherwise custom menus can also be added to your site by using the Custom Menu widget.