As you can see the links above are multi-level and you can have categories and its subcategories too placed in it, to make your menu deep to any level.All the Linking text above in red are Main Menu Items, In blue are Links in menu Itmes and in green are the Sublinks of Links Items.So you can make your top menu as you like.I am just explaining the format of defining it so that you can edit or make it very easily.

Making of Menu links of your own.Just define below format first :-