Web start-up unveils semantic search tool

Powerset on Sunday unveiled tools for searching Wikipedia that use conversational phrasing instead of keywords, marking the first step of its challenge to established web search services such as Google.

Powerset's technology breaks down the meaning of words and sentences into related concepts, freeing users from always needing to type the exact words they want to find.

The closely watched Silicon Valley start-up is offering a way of searching millions of entries in Wikipedia's online encyclopedia, helping users find detailed answers to questions rather than isolated links that require further research.