A key distinguishing feature of VisTrails is a comprehensive provenance infrastructure that maintains detailed history information about the steps followed and data derived in the course of an exploratory task: VisTrails maintains provenance of data products, of the workflows that derive these products and their executions. This information is persisted as XML files or in a relational database, and it allows users to navigate workflow versions in an intuitive way, to undo changes but not lose any results, to visually compare different workflows and their results, and to examine the actions that led to a result. It also enables a series operations and user interfaces that simplify workflow design and use, including the ability to create and refine workflows by analogy and to query workflows by example.
VisTrails supports the creation and execution of workflows. It allows the combination of loosely-coupled resources, specialized libraries, grid and Web services. The released version comes with support for several packages including, VTK, Image Magick, Web Services, and pylab. You can also download packages contributed by our users, as well as create your own packages/modules. Workflows can be run interactively, through the VisTrails GUI, or in batch using a VisTrails server.
VisTrails 1.0 was released in October 2007. Since then, the system has been downloaded thousands of times. VisTrails is written in Python and it uses the multi-platform Qt library for its user interface. It runs on Mac, Linux and Windows.