| Class | Description |
|---|
| AppDomain | Represents an isolated environment where applications are executed. |
| AppParameters | Provides methods for communicating between current application domain and another application via the parameters. |
| Array | Provides methods for manipulating arrays.This class is the base class for all arrays. |
| Attribute | |
| AttributeUsageAttribute | |
| AutoCleanAttribute | |
| Boolean | Represents a Boolean value. |
| Char | Represents a Unicode character. |
| Convert | Converts a base data type to another base data type. |
| DateTime | Represents an instant in time, expressed as a date and time of day. |
| Delegate | Represents a delegate, which is a data structure that refers to a static method or to a class instance and an instance method of that class. |
| DisposableAttribute | |
| DisposingAttribute | |
| Double | Represents a double-precision floating point number. |
| Enum | Provides the base class for enumerations. |
| Environment | Provides information about the current environment and platform. |
| EventArgs | EventArgs is the base class for classes containing event data. |
| ExternalInterface | Provides methods for the interaction between the current application and the external interface. |
| Guid | Represents a globally unique identifier (GUID). |
| Int32 | Represents a 32-bit signed integer. |
| Math | Provides constants and static methods for trigonometric, logarithmic, and other common mathematical functions. |
| Object | Supports all classes in the framework class hierarchy and provides low-level services to derived classes. This is the ultimate base class of all classes. It is the root of the type hierarchy. |
| Random | Represents a pseudo-random number generator. |
| StartParameters | Represents a collection of name-and-value pairs that are organized based on the hash code of the name. |
| String | Represents text. |
| TimeZone | Represents a time zone. |
| Type | Represents type declarations: class types, interface types, array types, value types, and enumeration types. |
| UInt32 | |
| Version | Represents a version number. |
| Void | Indicates a method that does not return a value. |