A web tool hailed as a significant rival to search giant Google has gone live to the public.

Wolfram Alpha is called a computation knowledge engine rather than a search engine and wants to change the way people use online data.

It aims to give people direct answers to queries rather than send them to other sites where they may find what they are seeking.

The system is the brainchild of British-born physicist Stephen Wolfram.

Wolfram Alpha was unveiled in late April and since then has been publicly demonstrated and some people have had a chance to run queries through it.

Typically the results it returns are annotated pages of data rather than a simple list of other sites that might help resolve a user's query.

For example, if asked about the weather in Manchester it would present a graph of average temperatures, rainfall and other salient data.

The computational horsepower behind the main site works out answers to question as they are put by grabbing data from databases and consulting feeds of relevant information.

Wolfram Alpha can be asked known facts, such as the height of mountains, or be asked to generate new information such as up to date figures for a nation's GDP.

It can also handle complicated mathematical queries, plot statistics and produce charts of natural events.

The data it consults is chosen and managed by staff at Wolfram Research who ensure it can be displayed by the system. Behind the scenes Wolfram Alpha has about 10,000 CPUs spread across five data centres that it draws on when generating answers.

During a demonstration at Harvard University's Berkman Center for Internet and Society, Dr Wolfram said: "Our goal is to make expert knowledge accessible to anyone, anywhere, anytime."

Dr Wolfram played down talk that the system would be a Google killer and instead presents it as a way for people to get more out of the information on the web.

The final tuning and testing of the system was webcast live during the weekend before the official launch.

Prior to the start of the webcast and final testing, Theo Grey, co-founder of Wolfram Research, said: "If we do melt down when we go live it will not be for lack of effort, or any sort of naive idea of how many queries we might get. It will be because of overwhelming response."

Reference: http://news.bbc.co.uk/2/hi/technology/8052798.stm