Personalization Personalization is becoming an essential part of many varieties of Web sites, including portals and shopping sites. Some available ASP.NET personalizable features include user profiles, themes, error pages, favorite links, and position of UI panels. The ASP.NET user profile is designed for persistent storage of this structured data through a type-safe API. To use personalization features, the developer defines his own model of personalized data and ASP.NET parses and compiles that model into a class. The storage of personalized settings occurs on a per-user basis and is preserved until an administrator deletes it.