some  of  the  most  common  application  errors  involving  memory  leaks  and invalid memory references. It manages all references to objects and releases them when they are no longer in use. In a nutshell, the automatic memory management helps the application clean up after itself. The  common  language  runtime  also  should  increase  application  perfor- mance. This may be accomplished in two ways: just-in-time (JIT) compliers and server-side applications. The JIT compilers are used to compile all man- aged code to native machine binary code at execution. Server-side applications can  house  application  logic  and  business  rules  on  .NET  Enterprise  Servers such  as  Internet  Information  Server  (IIS)  and  SQL  Server.  This  allows  the consolidation of application logic and business rules in a more maintainable environment and permits execution closer to dependent resources. For many applications this will result in not only reduced maintenance requirements but increased responsiveness. .NET Framework Class Library The .NET Framework class library is a collection of reusable classes, or types, that tightly integrate with the common language runtime. .NET applications benefit  from  using  and  extending  or  inheriting  the  functionality  from  the classes and types available in the class library. The class library is very hierar- chical  and  well  organized,  as  shown  in  Figure  1.2.  It  starts  with  the  most generic classes and continues to build down to classes with very specific and precise functionality. Although this library is extensive, its organization makes it easy to learn and use. In an age of ever-growing technology it is refreshing to  see  a  new  technology  and  a  new  architecture  that  promise  a  reduced learning curve. This model also makes it easy for third-party components to be integrated easily with the existing class library. Figure 1.2 The .NET Framework class library is hierarchical in nature and goes from the more generic to the more specific. Unified Programming Model SYSTEM I/O DATA ADO INTERNAL SQL SQL TYPES SECURITY CRYPTOGRAPHY PERMISSIONS POLICY PRINCIPAL .NET Class Framework ISOLATED STORAGE Introduction to the .NET Framework 7 04235946 Ch01.F  12/11/02  11:43 AM  Page 7