This was one of the most powerful search engines in the nineties. It was originally developed by the now defunct Digital Equipment Corporation (DEC). The engine emerged from a project which originated in one of the DEC research labs that had developed very powerful software for keeping track of emails. Reputedly the name came from the fact that, when the project was discussed, the whiteboard that was used contained the unerased second word of Palo Alto which was then modified and concatenated with Vista. It still exists but has been superseded by other search engines such as the Google search engine.