The Universal Messaging JavaScript API is a pure JavaScript solution. This allows developers to use JavaScript and HTML to build Ajax/Comet clients which can publish and subscribe to Universal Messaging channels, and asynchronously receive events in realtime:

Our JavaScript API is popular because it works without plugins or infrastructure workarounds, using only the browser's built-in JavaScript engine.

The Universal Messaging Silverlight API is an C# .NET API allowing the rapid development of publish/subscribe RIA clients. These clients can be run within a browser:

The Universal Messaging Java client APIs can be used for standalone Java applications, but can also be used in the browser as either Applets or Java Webstart applications.

Note that the above Universal Messaging Java links are for web-based applications. Universal Messaging Java APIs can also be used for enterprise clients and servers, as well as mobile applications.