ActionsResolver A resolver to return all IAction objects

 ApplicationContext the Umbraco Application context

 CacheHelper Class that is exposed by the ApplicationContext for application wide caching purposes

 ConcurrentHashSet`1 A thread-safe representation of a . Enumerating this collection is thread-safe and will only operate on a clone that is generated before returning the enumerator.

 CoreBootManager A bootstrapper for the Umbraco application which initializes all objects for the Core of the application

 DatabaseContext The Umbraco Database context

 DelegateEqualityComparer`1 A custom equality comparer that excepts a delegate to do the comparison operation

 DisposableTimer Starts the timer and invokes a callback upon disposal. Provides a simple way of timing an operation by wrapping it in a using (C#) statement.

 HideFromTypeFinderAttribute Used to notify the TypeFinder to ignore any class attributed with this during it's discovery

 MonitorLock Provides an equivalent to the c# lock statement, to be used in a using block.

 ObservableDictionary`2 An ObservableDictionary

 PluginManager Used to resolve all plugin types and cache them and is also used to instantiate plugin types

 ReadLock Provides a convenience methodology for implementing locked access to resources.

 TopologicalSorter Topological Sort algorithm for sorting items based on dependencies. Use the static method TopologicalSorter.GetSortedItems for a convenient way of sorting a list of items with dependencies between them.

 UpgradeableReadLock Provides a convenience methodology for implementing locked access to resources.

 WriteLock Provides a convenience methodology for implementing locked access to resources.

 XmlHelper The XmlHelper class contains general helper methods for working with xml in umbraco.

 Attempt`1 Represents the result of an operation attempt.

 IconPickerBehaviour

 MacroErrorBehaviour

 RenderingEngine

 StringAliasCaseType

 Attempt Provides ways to create attempts.

 Constants Constants all the identifiers within the Umbraco core.

 DateTimeExtensions

 DelegateExtensions

 Enum`1 A very useful class for parsing, enumerating and querying Enum objects

 EnumerableExtensions Extensions for enumerable sources

 HttpContextExtensions

 IfExtensions Extension methods for 'If' checking like checking If something is null or not null

 IntExtensions

 Mandate Helper class for mandating values, for example on method parameters.

 ObjectExtensions

 SemVersionExtensions

 StringExtensions String extension methods

 SystemUtilities Static helper methods for returning information about the current System

 TypeExtensions

 TypeFinder A utility class to find all classes of a certain type by reflection in the current bin folder of the web application.

 UriExtensions Provides extension methods to .

 ApplicationEventHandler A plugin type that allows developers to execute code during the Umbraco bootup process

 DisposableObject Abstract implementation of IDisposable.

 UmbracoApplicationBase The abstract class for the Umbraco HttpApplication

 IApplicationEventHandler Custom IApplicationStartupHandler that auto subscribes to the applications events

 IBootManager A bootstrapper interface for the Umbraco application

 IDisposeOnRequestEnd Any class implementing this interface that is added to the httpcontext.items keys or values will be disposed of at the end of the request.