Taverna 2.1 Workbench is the latest version of the Taverna Workbench. It is highly recommended that you use this version if you are new to Taverna, or to migrate to this version if you have used Taverna Workbench before.
Taverna 1.7.2 Workbench, the latest version the Taverna 1.x Workbench series, is still available to download. Users are recommended to switch to Taverna 2.1 Workbench where possible.
Taverna Server is the remote workflow execution service that enables you to set up a dedicated server for executing workflows remotely. Taverna Server uses the Taverna 1.7.x API. A new version of the Server, updated to use the Taverna 2.1 codebase, will be released in 2010 (please refer to the Taverna Roadmap for details).
