.Net Framework Class Library

.Net Framework Class Library consist of predefined reusable classes, interface and types. It also provides core programming features such as Reflection, File IO, XML, Collections etc. All the core classes interface and types can be used with any .NET Framework programming languages such as C#, VB.NET, J# to develop complex enterprise window and web application.

In order to use functionality of base classes you must need to include namespace on which the calling function is belong. For example, System namespace is require to for value and reference type, System.Collections namespace is require to use Lists, hashtables and dictionaries in you program.

The below table contains a list of each class of the base class library and a brief description of what they provide.

SystemThis namespace includes data types, console, match and arrays, etc.
System.CodeDomThis namespace responsible for creation of code at runtime and the ability to run it.
System.CollectionsThis namespace contains Lists, stacks, hashtables and dictionaries
System.ComponentModelThis namespace provides licensing, controls and type conversion capabilities
System.ConfigurationThis namespace is used for reading and writing program configuration data
System.DataThis namespace is responsible for ADO.NET
System.DeploymentThis namespace is for upgrading capabilities via ClickOnce
System.DiagnosticsThis namespace provides tracing, logging, performance counters, etc. functionality
System.DirectoryServicesThis namespace is used to access the Active Directory
System.DrawingThis namespace contains the GDI+ functionality for graphics support
System.EnterpriseServicesThis namespace for working with COM+ from .NET
System.GlobalizationThis namespace is supports the localization of custom programs
System.IOThis namespace is provides connection to file system and the reading and writing to data streams such as files
System.LinqThis namespace responsible for execution of LINQ queries
System.Linq.ExpressionsThis namespace contains delegates and lambda expressions
System.ManagementThis namespace provides access to system information such as CPU utilization, storage space, etc.
System.MediaThis namespace contains methods to play sounds
System.MessagingThis namespace is used when message queues are required within an application, superseded by WCF
System.NetThis namespace provides access to network protocols such as SSL, HTTP, SMTP and FTP
System.ReflectionThis namespace is used to read, create and invoke class information.
System.ResourcesThis namespace is used when localizing a program in relation to language support on web or form controls
System.RuntimeThis namespace contains functionality which allows the management of runtime behavior.
System.SecurityThis namespace provides hashing and the ability to create custom security systems using policies and permissions.
System.ServiceProcessThis namespace is used when a windows service is required
System.TextThis namespace provides the StringBuilder class, plus regular expression capabilities
System.ThreadingThis namespace contains methods to manage the creation, synchronization and pooling of program threads
System.TimersThis namespace provides the ability to raise events or take an action within a given timer period.
System.TransactionsThis namespace contains methods for the management of transactions
System.WebThis namespace is used for ASP.NET capabilities such as Web Services and browser communication.
System.Windows.FormsThis namespace containing the interface into the Windows API for the creation of Windows Forms programs.
System.XmlThis namespace provides the methods for reading, writing, searching and changing XML documents and entities.