The namespace provides a programming interface for modern HTTP applications.

The namespace is designed to provide the following: HTTP client components that allow users to consume modern web services over HTTP. HTTP components that can be used by both clients and servers (HTTP headers and messages, for example). This provides a consistent programming model on both the client and the server side for modern web services over HTTP. The namespace and the related namespace provide the following set of components: - the primary class used to send and receive requests over HTTP. and - HTTP messages as defined in RFC 2616 by the IETF. - HTTP headers as defined in RFC 2616 by the IETF. - HTTP handlers responsible for producing HTTP response messages. There are various HTTP message handles that can be used. These include the following. - A class used to plug a handler into a handler chain. - A simple to class to derive from that supports the most common requirements for most applications. - A class that operates at the bottom of the handler chain that actually handles the HTTP transport operations. - A specialty class that operates at the bottom of the handler chain class that handles HTTP transport operations with options that are specific to the object. The contents of an HTTP message corresponds to the entity body defined in RFC 2616. A number of classes can be used for HTTP content. These include the following. - HTTP content based on a byte array. - HTTP content of name/value tuples encoded using application/x-www-form-urlencoded MIME type. - HTTP content that gets serialized using the multipart/* content type specification. - HTTP content encoded using the multipart/form-data MIME type. - HTTP content based on a stream. - HTTP content based on a string. If an app using the and namespaces intends to download large amounts of data (50 megabytes or more), then the app should stream those downloads and not use the default buffering. If the default buffering is used the client memory usage will get very large, potentially resulting in substantially reduced performance. Classes in the and namespaces can be used to develop Windows Store apps or desktop apps. When used in a Windows Store app, classes in the and namespaces are affected by network isolation feature, part of the application security model used by the win8. The appropriate network capabilities must be enabled in the app manifest for a Windows Store app for the system to allow network access by a Windows store app. For more information, see the Network Isolation for Windows Store Apps.