For each product, or sometimes for each set of tools within a product, there is a small set of personas, one of whom is the primary focus for the design. There are also what's called a secondary persona, where the character is not the main target of the design, but their needs should be met and problems solved if possible. They exist to help account for further possible problems and difficulties that may occur even though the primary persona is satisfied with their solution. There is also an anti-persona, which is the character that the design is specifically not made for.