An album holds your photos and can have various settings including : theme, privacy mode, and many other functionality and layout settings. A new account has a single album by default, but you can at any time create new albums.
You can change the order of albums on your homepage or in any category. Clicking the "Organize" button - accessible when you hover the mouse pointer over the albums section :
will open the Organizer where you can change the order of your albums by dragging them (for more see the Organizer - Ordering article). Alternatively, you can access the Organizer via "Organize" >> "Organizer".
You can move an album to a different category using the same "Organizer"/"Organize" options. Starting the Organizer will display a tree containing all your albums and categories in the navigation panel. You can move albums between categories by dragging them. You can also drag multiple albums from the contents panel on the right to the navigation panel on the left.
You can create a new album in a chosen category using the same "Organizer"/"Organize" options as well as using the "New Album" choice from the Album Tools roll-down menu (for more see the "Creating new albums" article).
What can I do next? You can take a look at the other topics in the "Getting Started" category.