The Account Details screen is made up of a number of Panels. A collection of Panels is called a Panel View. Panels can be used on more than one Panel View. There is no limit to the number of Panels that can be created. Panels can consist of a range of items from individual Fields to Contact History lists.
Click here for information on Panel setup.
Click here for information on Panel Views setup.
Click here for information on Advanced Panel Configurations.